Energy Code Workbook v0.95.pdf

ENERGY CODE TRAINING FOR ARCHITECTS AND ENGINEERS

2015 IECC

COPYRIGHT © 2015 New York State Energy Research and Development Authority (NYSERDA). All rights reserved.

DISCLAIMER None of the parties involved in the funding or creation of the PowerPoint presentation and course manual—including NYSERDA, and Urban Green Council and its contractors—assume any liability or responsibility theofuser or any third parties for the accuracy, completeness, orto use or reliance on any information contained in the PowerPoint presentation and course manual, or for any injuries, losses or damages (including, without limitation, equitable relief) arising from such use or reliance. Although the information contained in the PowerPoint presentation and course manual is believed to be reliable and accurate, all materials are provided without warranties of any kind, either express or implied, including but not limited to warranties of the accuracy or completeness of information contained, merchantability, or the fitness of the information for any particular purpose. As a condition of use, the user pledges not to sue and agrees to waive and release NYSERDA and Urban Green Council and its contractors from any and all claims, demands, and causes of action for any injuries, losses, or damages (including without limitation, equitable relief) that the user may now or hereafter have a right to assert against such parties as a result of the use of, or reliance on, the PowerPoint presentation and the course manual. Urban Green Council 55 Broad St. New York, NY 10005

2 DRAFT FOR REVIEW: NOT PROOFREAD

CONTENTS PAGE 4

Introduction

11

Commercial Energy Conservation Code C401 C402 C403 C404 C405 C406 C407 C408 C501

44

General Building Envelope Requirements Building Mechanical Systems Service Water Heating Electrical Power and Lighting Systems Additional Efficiency Package Options Total Building Performance System Commissioning Existing Buildings

Residential Energy Conservation Code R401 General R402 Building Thermal Envelope R403 Systems R404 Electrical Power and Lighting Systems R405 Simulated Performance Alternative R406 Energy Rating Index R501 Existing Buildings

66

Documentation and Inspections

71

Acknowledgements


INTRODUCTION Welcome to Urban Green Council’sConquering the Energy Code course. In this course you will learn the core principles of the 2015 IECC in order to design compliant and better-performing buildings. Building on the success of GPRO, NYSERDA has enlisted Urban toover develop and deliver Conquering theGreen EnergyCouncil Code to 5,000 architects and engineers across New York state. As one of these design professionals, you will learn the provisions of and the science behind the Energy Code as well as how improved compliance brings benefits to your practice, career, and community. The Energy Code is one of the most important tools for creating more energy-efficient and sustainable buildings across New York State, and architects and engineers are the key to deploying it effectively. Passing stricter energy codes has done more to create efficient, safe, healthy, and sustainable buildings than any other strategy. However, for these codes to be effective, the design community must be motivated to implement them properly. It is no longer enough to just be aware of energy code requirements—as professional architects and engineers, you will also need to change your work practices and persuade owners to increase their expectations for building performance. The course materials will provide you with the professional knowledge required to comply with the Energy Code. This course is an overview that will show you how to work with the Code, while encouraging you to pursue design options that exceed it. Conquering the Energy Code examines the energy-using systems of commercial and residential buildings in accordance with the updated 2015 IECC. The course explains the provisions within the context of the various energy code compliance paths— from the building thermal envelope through the selection of building mechanical systems.

Though it is meant to be a companion to the in-person Conquering the Energy Code course, this manual follows the chronological organization of the code for ease of use later as a desk reference. While this manual is not a substitute for the code, we hope that it helps to facilitate familiarity with the provisions of the 2015 IECC.


Upon completion of this course you will be able to: • Describe the structure and rationale behind the energy code • Differentiate the various compliance pathways and describe the requirements for compliance • Recognize the interdependence ofthe building envelope, mechanical and lighting systems and their impacts on energy consumption • Sharpen communication and coordination practices as related to clients, the design team, code officials and the construction team to remove barriers to compliance And finally, Conquering the Energy Code aims to inspire professionals throughout New York State to design buildings that not only comply with the new energy code but that perform at levels far exceeding it.

N O I T C U D O R T N I


ENERGY CODE BASICS IMPROVEMENTS TO BUILDING ENERGY USE SINCE 1975 The first energy efficiency standard for buildings, ASHRAE 90-1975, was srcinally developed in response to the OPEC oil embargo energy crisis of the early 70s. Although the priority for most cities has now shifted to carbon emissions, for the first time, Americans were starting to think about the energy consumption of their infrastructure and what they could do to reduce it. Since then, energy codes have improved dramatically—a building approved under today’s energy code will use almost half of the energy of a building constructed in 1975—and designers have gained a better understanding of how all building systems work together to affect energy use as an integrated whole. The 201 5 IECC significantly improves building performance while taking into account the cost of design and construction so that new requirements are not burdensome to the building industry. The code strengthens energy requirements for insulation, air barriers and window construction. New and retrofitted buildings will be better sealed and insulated, reducing the energy required to keep them comfortable and well-lit.

CHALLENGE FOR THE INDUSTRY As energy codes continue to improve, commercial and residential buildings will soon be held to much higher energy performance standards. The New York State Energy Research & Development Authority (NYSERDA) estimates that new construction will be required to meet net-zero standards by 2028. National building trends are leading to net-zero standards for new residential construction within the next two decades. In order to meet today’s code and net-zero standards by 2028, the industry is going to have to change its design and construction practices. (100% = 1975 building energy use)

90

) 0 80 0 1 = e 70 s U 5 60 7 9 1( I 50 U E d 40 e z li a 30 m r o 20 N

IECC updated year ASHRAE updated year

MEC 1983/86

100 Std. 90-1975

Std. 90A-1980

MEC 1992/93 MEC 1995

IECC 1998

IECC 2004/06

Std. 90.1-1999

Std. 90.1-1989

IECC 2009

Std. 90.1-2001 Std. 90.1-2004 Std. 90.1-2007

Std. 90.1-2010

Today’s buildings will use almost half the energy of a code-compliant 1975 building

IECC 2012

IECC 2015 Std. 90.1-2013

10

(0% = NetZero Energy Building)

0 1975

1980

1985

1990

1995

2000

2005

2010

2015

2020

2025

2030

Year

NET-ZERO ENERGY BUILDING A zero net energy building (ZNE), also known as a net-zero energy (NZE) building, is a building with very low loads and a renewable energy supply, such as photovoltaic (PV) panels. Of course the PV will supply no energy at night and less energy in the winter, when the building consumes grid electric power. Conversely, when there is excess energy, it is fed back to the grid by the building systems.To qualify as an NZE building, the total energy used by the building in a year must be less than or equal to the renewable energy created on site in the same year.


BENEFITS AND TRENDS

Buildings that are designed to use less energy save the occupant money over the long term. The report, “National Cost-Effectiveness of the Residential Provisions of the 2015 IECC” by the Pacific Northwest National Laboratory (PNNL), determined that “residential buildings constructed to the prescriptive and mandatory requirements of the 2015 IECC save homeowners money over the life of their homes. Although many believe that improving building performance will increase costs and delay projects, many mature green design and construction teams can design forto less cost than lower-performance buildings due team efficiencies, right-sizing equipment, and creating less waste. A building’s energy performance is not a significant indicator of construction cost as compared to building size, occupancy, or level of finishes.

THE COST OF NON-COMPLIANCE

Code Non-Compliant Residential

Code Non-Compliant Commercial

8% of annual energy cost is

5% of annual energy cost is

duelost to waste. savingsCumulative over a building’s 50-year lifetime:

duelost to waste. savingsCumulative over a building’s 20-year lifetime:

$31,659

$480,000

Figures from American Council for an Energy Efficient Economy (ACEEE), 2012.Improved Code Enforcement: A Powerful Policy Tool Lessons Learned from New York State

+/-

Research conducted by McGrawHill1 shows that the construction market is quickly moving towards high-performance commercial and residential buildings. The number of green construction projects increases annually; by current estimates, green buildings will represent 55% of all commercial and institutional construction and 38% of all residential construction in 2016. Even if energy costs aren’t a high priority for the client or building owner, everything designed to save energy (especially on building envelopes) also improves comfort and productivity. 1

McGraw-Hill, 2013.Dodge Construction

Green Outlook

HIGH PERFORMANCE BUILDINGS AND PRODUCTIVITY

+/-


A study by the Harvard T.H. Chan School of Public Health, titled “The Impact of Green Buildings on Cognitive Function” found that by improving the indoor air quality and ventilation to levels typical of high performance buildings, cognitive function (i.e. productivity) of workers improved by 61% in green building conditions and 101% in enhanced green building conditions.


ENERGY CODES USE A SYSTEMS-BASED APPROACH CLIMATE ZONES DETERMINE CODE REQUIREMENTS

Energy code sets different requirements depending on a county’s Climate Zone (CZ), as colder areas will require more insulation and heat-conserving measures. There are three different climate zones in New York State, with CZ 4 being the mildest and CZ 6 being the coldest. Because New York is a heating-dominated climate, code requirements will focus more around measures that conserve heat in the winter rather than measures for cooling in the summer.

Climate Zone 6 Climate Zone 5 Climate Zone 4

The climate zones of New York State

CLIMATE PARAMETERS AFFECT ENERGY DESIGN SOLAR RADIATION

Climate parameters affect the way a building uses energy, so a high-performance building in New York’s climate—with its wet, humid summers and cold, dry winters—will be designed quite differently from a highperformance building in other parts of the country: • Outside temperatureaffects heat gain and loss. This determines how much insulation is needed on the building’s thermal envelope. • Solar radiation adds heat to the building. Window performance plays a large role in regulating unwanted heat gain from solar radiation. • Daylight allows less artificial lighting to be used, but may increase glare, affecting resident comfort. • Moisture from humidity affects occupant health and comfort, and poorly-managed moisture infiltration will considerably damage a building’s envelope. • Wind increases infiltration andleads to heat gain or loss. As these factors change throughout the year, a building must be designed for optimal performance in all conditions. For example, high-performance windows


MOISTURE

DAYLIGHT/GLARE

HEAT/COLD WIND

Climatic factors greatly affect how the building must be designed in order to maximize energy savings

that block solar heat gain in the summer will also block desired heat gain in the winter. A white roof will lower heat gain in summer but undesirably lower heat gain in the winter. Factors that affect energy use throughout all four seasons must be considered. The challenge is to balance building systems that keep building interiors comfortably consistent by using the


WHOLE BUILDING APPROACH

The “whole-building approach” is the idea that all systems such as lighting, HVAC, plumbing, and envelope are all interconnected and work together in an efficient building. Changing one aspect of the building envelope may have unintended consequences elsewhere. For example, increasing the efficiency of the thermal envelope will lead to a lower demand on the boiler, but If the boiler is already over-sized, it will short-cycle more and run less efficiently. Conversely, swapping out inefficient, heatproducing incandescent light bulbs with LEDs will lower the amount of heat in the building, and the boiler will have to work harder to compensate. Consider all of a building’s systems at once and be aware of how changes in one system may affect other systems. The ultimate goal issynergy between systems, meaning that each system works in cooperation with the others, creating a result that is greater thanthe sum of its parts. For example, upgradinga building’s thermal envelope while simultaneously installing a smaller, more efficient boiler will have a positive effect on the building’s performance that would not be possible separately. A B

Solar Thermal

Provide renewable solar water heating

Rain Water Harvest Uses water for toilets + garden

C

White Roof or Green Roof Reduces urban heat island effect

D

Sun Control Devices Reduce solar heat gain in summer, direct daylight into room to lower lighting loads

A

E

C

Condensing Boiler Reduces energy use for heat + hot water supply

B

F

Heat Recovery Ventilation or Controlled Exhaust Ventilation Reduces energy use

G D

Cogeneration Uses both heat + electric power from local generator

E

H

High Performance Windows Increase comfort + save energy

G

I

FSC Wood Flooring Supports sustainable forestry

J

Occupancy + Daylighting Controlled Lighting Reduces energy use, improves indoor environment

K

Low Water/Dual-Flush Toilet Reduces water use

L

Continuous High R-value Insulation Increases comfort + saves energy

M

K J

Recycled Ceiling Tiles Reduce resource use

N

ENERGY STAR Appliances Reduce electrical + water use

O

Low VOC Green Cleaning Products Improve indoor air quality

P

Meters + Submeters Increase awareness of energy + water use

N

Q

P

Recycling Reduces resource use

R

Access to Mass Transit Reduces energy use

S

Greywater System Recycles water to toilets + garden

P

POTABLE WATER

S


BLACK WATER

The whole building approach sees a building as an interconnected network of systems that all affect each other. Changes in any one system can impact how other, seemingly unrelated systems, function as well.


COORDINATION AND COMMUNICATION INTEGRATED DESIGN APPROACH

CHANGES EARLIER IN THE PROJECT ARE MORE COST EFFECTIVE

Integrated design is when project team members from all disciplines work together early and often throughout the project design process.

The chart below shows how the cost of design changes increases as the project progresses. Therefore, it is more cost-effective to spend more effort on design decisions in the beginning of the project. In integrated design, early effort in the design phase can avoid the costly mishaps that can crop up later in traditional design process. What would have become a change order can be avoided by early communication with all the team members. It can help you fix issues before they become expensive.

• Involvement of the construction team during the design process reduces construction errors. • Coordinated team effort can identify impractical design elements. • Early involvement of the operations team during construction will ensure that the building operates as designed. Integrated design is a collaborative process that engages all members of the team from start to finish, putting emphasis on full life-cycle costs and benefits as opposed to up-front costs. Systems are considered in relationship to others, allowing for full optimization.

Optimal time for energy decisions

In the integrated design approach, the entire team works with the owner andare each other at tothe ensure that complications and redundancies spotted beginning of the process and not when construction has already begun.

This curve demonstrates that the ability to control costs and to make design changes is easiest at the beginning of the process, rather than later on when it becomes much more difficult and expensive.

Future Occupants Product Suppliers

Engineers Contractor

Owner

Architects

Trade/Design Specialists

Project Manager

Energy Professional Building Staff


Commissioning Agent



MILESTONES FOR COMMUNICATION Thorough team collaboration allows information to be shared early for better energy performance and energy code compliance. Communication should be facilitated within each phase of building design—this helps to ensure that systems work harmoniously and efficiently. Using the integrated design approach during the initial design phase is arguably the most important step in achieving high-performance buildings. Owner

Architect

Engineer

Energy Professional

Commissioning Agent

Construction Manager

Operator

Phase 1: Pre-Design

T R O F F E R E D L O H E K A T S

• • • • Ow

Ar

En

Set sustainability targets Establish a plan for future meetings, such as charrettes and stakeholder involvement Create pre-design report Create preliminary budget

Op

Phase 2: Schematic Design


Ow

Ar

En

EP

CM

O

• • • • • • •

Architect and engineer agree on which code to use Clearly establish goals and objectives Host sustainability charrettes Establish the feasibility of proposed technologies Create a preliminary energy analysis Create a preliminary financial estimate Create a schematic design report

Phase 3: Design Development


• • • • Ow

Ar

En

EP

CxA

CM

Perform modeling simulations on building system function, energy use, and resident comfort Create a design development report Create a detailed financial report Create preliminary commissioning report

O

Phase 4: Construction Documents


• • •

Ow

Ar

En

EP

CxA

CM

Create project specifications including performance criteria Establish a materials substitution policy Create documents that clearly outline the project’s sustainability features, how this will change the construction process, and whether any staff will need to receive additional training

Op

Phase 5: Construction


• • • • • Ow

Ar

En

EP

CxA

CM

Plan for an complete commissioning Train maintenance staff and operators Regular site meetings to verify that sustainable features are being properly installed Perform diagnostic tests while components are still accessible Create Operations and Maintenance Manuals

Op

Phase 6: Occupancy


• • • • Ow

Ar

En

EP

CxA

CM

O


Give building owner complete documentation on building features, including commissioning Develop tools for ongoing monitoring and benchmarking Host debriefing session Run training sessions on building sustainability features for staff and occupants

IECC COMMERCIAL PROVISIONS PAGE 13

C401 General

15

C402 Building Envelope Requirements

25

C403 Building Mechanical Systems

31

C404 Service Water Heating

32

C405 Electrical Power and Lighting Systems

38

C406 Additional Efficiency Package Options

39

C407 Total Building Performance

41

C408 System Commissioning

43

C501 Existing Buildings


L IA C R E M M O C

INTRODUCTION There are several important new provisions in 2015 IECC. Demandcontrolled ventilation and energyrecovery ventilation systems will now be required in more projects. Equipment efficiencies for HVAC equipment and service hot water systems have increased. Expanded lighting control requirements such as vacncy sensors, daylight responsive controls, and time-switch controls automatically reduce energy used for lighting. Most importantly, commissioning requirements include provisions for third party verification for HVAC and water heating systems, lighting and daylighting controls, as well as building thermal envelope testing.

2015 IECC will increase the energy efficiency of both commercial and residential buildings.


L IA C R E M M O C

C401 GENERAL C401.1 SCOPE All buildings that are not defined as Residential must comply with the Commercial Energy Conservation Code, including multifamily buildings more than three stories above grade. The mechanical systems in multifamily buildings may require the commercial code if the units are served by the same system.

L IA C R E M M O C

COMMERCIAL VERSUS RESIDENTIAL BUILDINGS Residential buildings include: Detached 1- and 2-family dwellings, Multiple single-family dwellings (townhouses), and Group R-2, R-3 and R-4 three stories or less above grade. Any building four stories or more—including multifamily residential buildings—must comply with the commercial code.

Residential

Commercial Commercial

Commercial

Commercial If filing for a building with both residential and commercial, it would all be included in one application and the designer would include two sets of data. One would cover the residential portions, and the other would cover the commercial. This is only necessary if the building is three stories or less and includes commercial and residential dwelling units.

DOES THE PROJECT NEED TO COMPLY WITH THE ENERGY CODE? Few buildings are exempt from the code. Designated historic buildings may be exempt if the design professional or preservation submits a report to the code official showing that compliance would interfere with the historic nature of the officer building (C501.6). Envelope requirements in some very low energy buildings, such as storage sheds, may be exempt. Some renovation projects may be exempt if they do not affect the energy use of the building. Please note, documentation that the building is exempt must still be submitted to the code official.


C401.2 APPLICATION To show compliance with the energy code, designers can select one of several compliance paths described below. Each path varies with the level of information required and the level of flexibility allowed. Generally, a designer can choose a “checklist-style” prescriptive path or submit an energy model that simulates the inflows and outflows of all energy used in the building, called the performance path. Typically, the more complex the compliance path is in terms of having to provide backup information, the more flexibility the designer will have designing the building and meeting the energy code. However, regardless of which compliance path the design team chooses, the building must comply with certain mandatory requirements.

CHOOSING A COMPLIANCE PATH Designers are permitted to comply using either of the following approaches described in 2015 IECC or ASHRAE 90.1-2013. Only one compliance path can be used per project. This means that you can’t use the prescriptive approach for one part of the project and performance approach for another. It also means that you can’t mix ASHRAE and IECC provisions in one filing.

within the envelope. For example, a building that does not meet the U-factor requirements for its windows or skylights may exceed the R-values of the walls or roof to compensate. COMcheck is a useful tool that aids designers to calculate envelope tradeoff efficiencies. COMcheck will automatically show if the design is compliant or which values are problematic. Though similar to 2015 IECC, ASHRAE 90.1-2013 has more mandatory provisions while the envelope requirements are less stringent. Generally speaking, the energy usage of a building designed to ASHRAE 90.1-2013 or 2015 IECC will be similar. 2015 IECC has an additional requirement, outlined in Section C406: Additional Efficiency Package Options The design team must pick one of the following options: Additional Efficiency Package Options:

1. More Efficient HVAC 2. Reduce Lighting Power Density (LPD) b y 10% 3. Enhanced Digital Lighting Control 4. On-Site Renewable Energy* 5. Dedicated Outdoor Air System 6. More Efficient Service Hot Water (SHW)

Unless otherwise noted all code provisions listed in this workbook will refer to 2015 IECC.

*If the project applies to only tenant spaces, it can comply with On-Site Renewable Energy only when the entire building is in compliance.

PRESCRIPTIVE PATH

Detailed information about the Additional Efficiency Package Options is included in section C406 in this workbook.

Using the prescriptive path for compliance means to accurately depict that the project satisfies a checklist of requirements included in the following sections: • C402: Building Envelope Requirements • C403: Building Mechanical Systems • C404: Service Hot Water Heating • C405: Electrical Power and Lighting Systems The prescriptive path is often the most straightforward approach and is fairly easy to use—the compliance tool can be as simple as a spreadsheet (called tabular analysis) or the free computer- or web-based compliance tool COMcheck. For renovation projects, the difficulty of energy modeling makes this approach desirable. However, this path is somewhat restrictive as there is little flexibility—the project either meets listed requirement or it doesn’t comply. For example: • The opaque areas of the envelope must meet minimum R-values for insulation, depending on the building’s climate zone. • HVAC and water heating equipment mustmeet or exceed minimum required efficiencies. • Energy used for lighting, calculated on a Watts/ SF basis, must not exceed values listed in the code on a building-wide or room type basis The prescriptive approach does allow minor tradeoffs 14 DRAFT FOR REVIEW: NOT PROOFREAD

PERFORMANCE PATH

Design teams with more complex projects or projects that cannot meet one or more of the prescriptive requirements must use the performance path. To comply, the team must create an energy model to prove the building’s energy use will not exceed the maximum allowed. Energy models are often used to help the design team make decisions early on. Since the energy model takes all of the building energy into account, the performance approach allows even more tradeoffs than the prescriptive approach, allowing tradeoffs to be made among and between systems. For example, if a building’s envelope exceeds the maximum-permitted prescriptive window-to-wall ratio requirement, the design team can compensate by specifying more efficient HVAC, water heating and lighting equipment than is required by code. When using the performance path, NYCECCC only allows compliance using ASHRAE 90.1-2013. However, either Section 11 (Energy Cost Budget Method) or Appendix G (Performance Rating Method) of 90.1-2013 may be used to demonstrate compliance. In New York State, only Section 11 is allowed when using the performance path in ASHRAE 90.1-2013.

L IA C R E M M O C

C402 BUILDING ENVELOPE REQUIREMENTS The building envelope is the physical barrier between the building’s conditioned interior environment and the outside. Efficient building envelopes prevent air leakage and moisture migration, heat gain and loss, and solar heat gain through windows and skylights. To create a comfortable indoor environment and minimize wasted energy, the energy code requires continuous air barriers, continuous insulation, and efficient windows. The following sections will explain the context behind each code provision and provide examples of how to comply.

IDENTIFYING THE BUILDING THERMAL ENVELOPE In the code, the Building Thermal Envelopeis “the basement walls, exterior walls, floor, roof and any other building elements that enclose conditioned space or provide a boundary between conditioned space and exempt or unconditioned space.” To maximize envelope performance, the thermal boundary (insulation) should be closely aligned with the air barrier (air sealing). It may seem obvious, but to confirm to the code officials that the building thermal envelope is continuous, it must be possible to draw the building thermal envelope on the construction drawings, without picking up the pencil.

GENERAL The thermal envelope and the air barrier should be both continuous and continguous. Air seal all joints, seams, and penetrations.

ROOFS R-value and Solar Reflectance Index (SRI) affects heat loss / gain.

ABOVE-GRADE WALLS R-value and Solar Reflectance Index (SRI) affects heat loss / gain.

Show detailed cross sections on construction documents that demonstrates how thermal bridging was avoided.

WINDOWS U-factor affects heat loss/gain. SHGC affects heat gain. VT affects daylighting. Operation affects natural ventilation.

BELOW-GRADE WALLS R-value affects heat loss / gain.

THERMAL ENVELOPE The thermal envelope and the air barrier should be both continuous and continguous.


E P O L E V N E : L A I C R E M M O C

The building envelope is the largest system that affects energy usage. Ensuring that the envelope functions effectively is a vital component to meeting new highperformance code requirements. Efficient building envelopes should be able to control three main factors: 1. Air leakage and moisture migration 2. Heat gain and loss when outside temperature is substantially different from indoor conditions 3. Solar heat gain through windows andskylights

CONTINUOUS AIR BARRIER PREVENTS AIR LEAKAGE Unwanted air moving into and out of buildings through cracks and penetrations in the envelope is called infiltration and exfiltration. Air leakage is the primary source of heat loss in buildings in cold climates. So just as you need to zip up your coat to stay warm in winter, the energy code requires continuous air barriers at all building envelope components.

To make sure that envelopes perform effectively, energy Traditionally, air leaks have been considered a source code requires: of fresh air. Since air flow would vary drastically with wind speed and heating system operation, this was an 1. Continuous air barriers and installation details for unreliable source of ventilation, as well as a source of most envelope components heat loss. With today’s tight envelopes, all commercial 2. thermal Continuous insulation at theat entire building and many residential buildings must have mechanical envelope including walls, ceilings, ventilation systems—often with heat recovery devices. floors and transitions between these components 3. Window and wall performance criteria

ADDED BENEFIT OF EFFICIENT ENVELOPES: BUILDING MAINTAINS TEMPERATURE EVEN IN A BLACKOUT In addition to energy efficiency, an added benefit of a high-performing building envelope is resiliency—it resists temperature fluctuations in the event of extreme weather or loss of power. This graph, taken from Urban Green Council’s report “Baby It’s Cold Inside,” shows what would happen inside a building with a low-performing envelope, a code-compliant building, and a high-performing building during an extended winter blackout. After a loss of heating, the temperature inside a typical single-family house would be 35°F three better. days. AAfter high-performing buildingpower, that has better windows, single-family fewer air leaks, andwould more insulation wouldafter do much three days without a high-performing house stay above 60°F. New York State has a climate with extreme winter and summer conditions, and especially in Western NYS where severe squalls threaten energy infrastructure, buildings can survive better when designed for energy efficiency. Buildings that are resilient mean that they can withstand weather volatility, as well as loss of power and extreme weather.

High-performing

Typical Outdoor Temp

Indoor temperatures during a winter blackout. Higher performing buildings have better windows, less air infiltration, and more insulation than a conventional building.



THERMAL BRIDGING Thermal bridging occurs when a poorly insulating material allows heat flow across a thermal barrier. To prevent thermal bridging you must provide a thermal break, such as continuous insulation, seen in the illustration to the right


Thermal modeling demonstrates how heat transfers through a thermal bridge (left) and how effective construction mitigates heat loss.

Thermal bridging at slab edge.

R-VALUES AND U-FACTORS

Interior sheathing

R-0.45

Cavity insulation

R-13.60

Exterior sheathing

R-0.45

Vapor retarder

R-0.06

Continuous insulation

R-7.50

Metal panel

R-0

Total: U-value = 1 / 22.06 =

R 22.06 0.045

R-Values can be found by adding the values of each wall component. To the U-factor, take the inverse of the total R-value.

The R-value is the capacity of a material to resist heat flow. A higher R-value is preferable because it means there is a higher capacity to resist heat flow. Much like layering clothes and a coat in winter to prevent heat loss from your body, you can add the R-values of separate elements to get a higher level of insulation. The total heat transfer must take two factors into account. The first is the total R value—the capacity of an assembly to resist heat flow based on the sum total of its layers. The R-value of a wall cavity is obtained by adding up the values of its individual parts, as seen in the illustration. The second is the U factor—the simultaneous heat transfer through various types of assemblies that make up the find building envelope. The U factor can be found by taking the inverse of the total R value. Unlike R-values, you cannot add U-factors.

R = 1/U


U = 1/R

C402.1 GENERAL The code provides 3 options for showing compliance:

C402.1.3 INSULATION COMPONENT R-VALUE-BASED METHOD COMPLIANCE METHOD #1: The R-Value method is the most straightforward approach. Designers show their proposed above- and below-grade walls, roofs, floors and slabs-on-grade meet the required R-values listed in Table C402.1.3. Note that the R-values vary based on climate zone and whether or not the building’s use falls under a Residential Use Group.

C402.1.4.1 THERMAL RESISTANCE OF COLDFORMED STEEL WALLS

The code includes correction factors to calculate the “effective R-value” for cavity insulation when installed in steel stud wall assemblies. For example, R-13 cavity insulation installed in a wall with 3 ½” metal studs at 16” on center will only provide R-5.98. This calculation is only necessary when using the pathway in C402.1.4.

When using blown-in insulation for ceilings/attics: • Use manufacturer’s settled R-value To prove compliance: • Installation thickness marker with 1” high numbers, facing attic access door, at least one per 300ft2 • Keep label(s) from insulation products • Show R-Value calculations • Keep photos of installation to show inspectors

OR C402.1.4 ASSEMBLY U-FACTOR, C-FACTOR, OR F-FACTOR-BASED METHOD COMPLIANCE METHOD #2: This method allows designers to make some envelope tradeoffs by calculating the U-factor (thermal transmittance), C-Factor (thermal conductance) and F-Factor (perimeter heat loss for slab on grade floors) for the various components and verifying that each complies independently. The values for a wide variety of commonly used materials and construction assemblies can be found in ASHRAE 90.1 Appendix A. The designer inputs the required values and the areas/lengths for each assembly. COMcheck is a useful tool to calculate these tradeoffs.


OR C402.1.5 COMPONENT

PERFORMANCE ALTERNATIVE COMPLIANCE METHOD #3: The Component Performance Alternative method is similar to the UA Alternative method in the Residential code. It allows more substantial envelope tradeoffs. If an envelope component doesn’t comply with the prescriptive requirement, this method gives even more wiggle room than the other two methods. Calculate the differences in thermal resistance between the proposed design of each component and the values listed in Tables C402.1.3 and C402.1.4. The code allows adding up all the differences and if they net to below zero, the opaque thermal envelope complies.


C402.2 SPECIFIC BUILDING THERMAL ENVELOPE INSULATION REQUIREMENTS C402.2.1 MULTIPLE LAYERS OF CONTINUOUS INSULATION BOARD This section requires staggering of insulation board when more than one layer is used. Chapter 3 has additional requirements regarding insulation: • C303.1.1 Building thermal envelope insulation requires a manufacturer’s certification confirming the installed R-value of each insulation material. To prove compliance, you must: »

Place installation thickness markers with 1” high numbers, facing attic access door, at least one per 300ft2

»

Keep label(s) from insulation products

»

Show R-Value calculations

»

Keep photos of installation to show inspectors

requires • C303.1.2 Insulation mark installation visible onsite confirmation of the insulation material’s manufacturer and R-value • C303.2.1 Protection of exposed foundation insulationrequires any exterior insulation to have rigid, opaque and weather-resistant protective covering


C402.2.2 ROOF ASSEMBLY • Provide minimum R-value at thinnest part of tapered insulation or use area-weighted U-Factor •

Skylight curbs should be insulated to the level of roofs or R-5, whichever is less

C402.2.3 THERMAL RESISTANCE OF ABOVE-GRADE WALLS An above-grade wall is defined as: A wall associated with the building thermal envelope that is more than 15% above grade and Any wall that is associated with the building thermal envelope—including walls not on the exterior of the building, such as a room that contains fuel-burning appliances. Table C401.3 specifies both cavity and continuous (ci) insulation. If the insulation requirement lists two values, the first value is cavity insulation, the second value is continuous insulation, so “13+7.5ci” means R-13 cavity insulation plus a minimum of R-7.5 continuous insulation. Make sure to check the footnotes in the code for valuable information about how to interpret the code.


C402.2.4 FLOORS Wood subfloor

To prevent heat loss at the walls, code requires that the insulation be in contact with the underside of the floor assembly.

Cavity insulation Sheathing

Exception:If the floor cavity insulation goes from top to

bottom on the perimeter near the walls, it is permitted to rest on the sheathing. Air gap

Entire floor cavity by perimeter walls is filled

C402.2.5 SLABS-ON-GRADE PERIMETER INSULATION

C402.2.6 INSULATION OF RADIANT HEATING SYSTEMS

Insulation may be installed on inside or outside of foundation wall.

It has always been good practice to insulate under radiant floor slabs, but now it is also required by code.

Insulation must extend: • To depth shown in table C402.1.3OR • To the top of the footing, whicheveris less OR • To bottom of slab and then horizontally to the interior or exterior for the total distance shown

• R-3.5 at all surfaces not facing heated space • The R-value of the insulation between the radiant heating system panels and the exterior must be equal to the R-value of the building thermal envelope

Exception: Perimeter insulation is not required where the slab-on-grade floor is lower than 24 inches below finished exterior grade

FLASHING SLAB

PROTECTION

SLAB SLAB

BOARD R-10 INSULATION

R-10 INSULATION

-10 INSULATION

Thermal break

hermal break

between slab and

etween slab and

foundation

oundation

Methods of insulating the slab



C402.3 ROOF SOLAR REFLECTANCE AND THERMAL EMITTANCE Cool roofs prevent solar heat gain in buildings and reduce the urban heat island effect (the tendency for urban areas to be much warmer than the surrounding climate). Because dark surfaces absorb solar energy and light surfaces reflect it, applying a light surface to the roof is a very inexpensive way to reduce heat gain in a building. This is required in New York City despite not being a 2015 IECC requirement for Climate Zones 4, 5 and 6. New York City’s Local Law 21 requires roofs with a slope of less than 17% to have a 75% of their area with a Solar Reflectance Index (SRI) of 78.

C402.4.1 MAXIMUM AREA 2015 IECC allows: • Vertical fenestration (windows):Maximum 30% Window-to-Wall Ratio (WWR) • Skylights: Maximum 3%of the gross roof area. WWR = Percentage of glazed area in entire building thermal envelope • “Window” is measured from rough opening and includes frame, sash, and other non-glazed window components (ASHRAE definition)

• IECC: WWR = % of gross above-gradewall area SRI 0 (Black):

SRI 100 (White):

SRI 78:

• ASHRAE: WWR = % gross exterior wall area including below-gradeas well as above-grade walls

C402.4 FENESTRATION Code-Compliant Window:

Lower = more efficient

U-0.38 = 1/0.38 =R-2.63 (CZ4, Table C402.4)

Lower = less solar heat gain

Metal-Framed Wall:

R-13 + R-7.5 ci (CZ4, Table C402.1.3)

Higher = more light in space

Lower = less air infiltration

Code regulates the ratio of window to walls because even the highest-performing windows are not nearly as energy efficient as a wall assembly.

A tag displaying the window assembly performance

Window selection should include consideration of each of the four performance factors, as they are all regulated by the code in various ways:

C402.4.1.1 INCREASED VERTICAL FENESTRATION AREA WITH DAYLIGHT RESPONSIVE CONTROLS

• U-Factor:The amount of heat that is conducted from the conditioned space to the outside. Look for a low U-Value to minimize heat loss from conduction. • Solar Heat Gain Coefficient: How much heat gain enters the window. Specialized coatings, the type of glazing, and material selection in the frame can influence the value of the SHGC. The code includes SHGC requirements depending on the orientation of the façade and the amount of shading on the window. • Visible Transmittance: How much light is transmitted through the window. Install windows with high visible transmittance to maximize the amount of natural light residents will have available. • Air Leakage:How much air will be able to escape through the assembly.

WWR

≤30%

>30%, ≤40%

>40%

Complies Must meet daylight Don’t comply prescriptively requirements to prescriptively comply prescriptively

• If the building is ≤30% WWR, it meets prescriptive requirements. • If the building is >30% and ≤40% WWR, it only meets prescriptive requirements if it meets daylighting requirements as well. If not, it must use the performance path. • Buildings with more than 40% WWR cannot meet prescriptive requirements and must comply with the performance path.



C402.4.1.1 INCREASED VERTICAL FENESTRATION AREA WITH DAYLIGHT RESPONSIVE CONTROLS

C402.4.1.2 INCREASED SKYLIGHT AREA WITH DAYLIGHT RESPONSIVE CONTROLS

The IECC WWR allowance increases to 40%only if all threeof the following criteria are met:

Similar to vertical fenestration, skylight area shall be permitted to be increased to 5% of the roof area provided daylight responsive controlsare installed in daylight zones under the skylights.

#1: Required Daylight Zone (per C405.2.3.1): • In buildings two stories or less, at least 50% of the net floor area is within a daylight zone

• In buildings threeor more stories above grade, at least 25% of the net floor area is within a daylight zone 75%

25%

C402.4.2 MINIMUM SKYLIGHT FENESTRATION AREA The code requires a minimum skylit area in certain large spaces with high ceilings located directly below a roof.

C402.4.2.1 LIGHTING CONTROLS IN DAYLIGHT ZONES UNDER SKYLIGHTS 50%

50%

All electric lights in daylight zones under skylights must have daylight responsive controls.

C402.4.2.2 HAZE FACTOR To avoid glare, skylights in certain spaces must have diffusing lens, have baffles, or be designed to provide indirect lighting only.

Percentages of the floor area that must be in a daylight zone

C402.4.3 MAXIMUM

U-FACTOR AND SHGC #2: Daylight Responsive Controls (per C405.2.3): • Lights must be controlled separately: »

In sidelight and toplight daylightzones

»

Zones facing different ordinal directions

U-factors and solar heat gain coefficients (SHGC) for windows and skylights must be less than or equal to values in Table C402.4.

C402.4.3.1 INCREASED SKYLIGHT SHGC

• Controls must be readily accessible and able to be configured from within the space

Skylights can have a maximum SHGC of 0.60 where located above daylight zones provided with daylight responsive controls.

• To avoid distracting occupants inoffices, classrooms, laboratories and library reading rooms, controls must:

C402.4.3.2 INCREASED SKYLIGHT U-FACTOR

»

»

Dim lights continuously from 100% to 15% of full light output Be capable of a complete shutoff

#3: VT ≥ 1.1x SHGC:

SHGC measures how much heat from the sun is transmitted. The higher the SHGC, the more solar heat gain is transmitted

Visible Transmittance (VT) ≥ 1.1 x Solar Heat Gain Coefficient(SHGC)

VT measures how much light comes through a window. The more visible light is transmitted, the higher the potential for daylighting


Skylights can have a maximum U-Factor of 0.75 where located above daylight zones provided with daylight responsive controls.

C402.4.3.3 DYNAMIC GLAZING Where dynamic glazing is used (any fenestration product that can change its performance properties, including U-factor, solar heat gain coefficient [SHGC], or visible transmittance [VT]) • The ratio of the higher to lower labeled SHGC shall be greater than or equal to 2.4 • Have automatic controls to modulate the amount of solar gain into the space in multiple steps.

C402.4.3.4 AREA-WEIGHTED U-FACTOR If calculating an area-weighted U-factor, each fenestration product category listed in Table C402.4 must be calculated separately. Individual fenestration products from different fenestration product categories—operable, inoperable, and entrance doors—can’t be combined to calculate area-weighted average U-factor.


C402.5 AIR LEAKAGE— THERMAL ENVELOPE (MANDATORY) The following section discusses specific, mandatory regulations to limit air leakage. These air sealing details must be shown on the drawing set in order to comply. The air barrier must align with the thermal barrier. The prescriptive path allows designers two ways to demonstrate there is an adequate air barrier. The first is to follow the prescriptive requirements, which specifies 8 provisions that must be met. The second is a testing option, which specifies that only 3 provisions be met if the envelope pressure is tested and meets an air leakage rate of less than 0.40 cfm/ft2.

C402.5.2 AIR LEAKAGE OF FENESTRATION Fenestration can have a maximum air leakage as listed in Table C402.5.2. The air leakage rate must be included on the manufacturer’s label. Note: Leave the label on the window until inspection is complete.

PRESCRIPTIVE OPTION TESTING OPTION • C402.5.1 Air barriers • C402.5.2 Air leakage of fenestration • C402.5.3 Rooms containing fuel-burning appliances

• Meets an air leakage rate of less than 0.40 cfm/ft2

• C402.5.4 Doors and access openings to shafts, chutes, stairways and elevator lobbies • C402.5.8 Recessed lighting

REQUIRED FOR BOTH • C402.5.5 Air Intakes, Exhaust Openings, Stairways and Shafts • C402.5.6 - Loading Dock Weatherseals • C402.5.7 - Vestibules

C402.5.1 AIR BARRIERS C402.5.1.1 AIR BARRIER CONSTRUCTION All air barriers must: • Be continuous • Be located on either the inside or outside of the building envelope • Be secure, durable and attached to the thermal boundary • Have all penetrations caulked or gasketed A successful air barrier design pays attention to the weakest spots: penetrations, window corners, joints, and discontinuous materials

C402.5.1.2 AIR BARRIER COMPLIANCE OPTIONS • Required air permeability of materials < 0.004 cfm/ft2 • Code lists 19 common building materials such as plywood, cement board and masonry that can be used as air barrier materials and assemblies


Fig X.XXX

C402.5.3 ROOMS CONTAINING FUELBURNING APPLIANCES As buildings are being built to tighter standards, there is less infiltration air available for open combustion appliances that draw air from the occupied space. In spaces with open combustion and/or fuel-burning appliances, 1. Appliances and combustion air opening must be located outside the building thermal envelope 2. Appliance must be enclosed in aroom isolated from the thermal envelope. The walls of this room must have the same R-value as the opaque above-grade walls for that climate zone 3. Ducts must be insulated to > R-8 when passing through conditioned space Direct vent appliances with both intake and exhaust pipes installed continuous to the outside do not have to comply with section C402.5.3.

C402.5.4 DOORS AND ACCESS OPENINGS Doors and access openings from conditioned space to shafts, chutes, stairways and elevator lobbies must be either gasketed, weatherstripped, or sealed. Building codes already require firestopping at these locations. The energy code adds the provision to seal them with gaskets and weatherstripping so air doesn’t leak out when they are closed.


C402.5.5 AIR INTAKES, EXHAUST OPENINGS, STAIRWAYS AND SHAFTS Code now requires motorized shutoff dampers (listed and tested) at outdoor air intakes and exhaust openings at stairway enclosures and elevator shaft vents (see C403.2.4.3)

C402.5.7 VESTIBULES Building vestibules prevent heat loss and gain. 1. All building entrances shall have an enclosed vestibule 2. Vestibule doors must beequipped with selfclosing devices 3. Interior and exterior doors should not need to be open at the same time Exceptions:

• Doors not for public use • Doors from a residential unit • Doors opening onto space < 3,000 ft2 • Revolving doors (vestibules are still required at doors adjacent to revolving doors) • If air curtain at door

C402.5.8 RECESSED LIGHTING Historically, recessed light fixtures have been a source of significant energy loss because they penetrate the building thermal envelope. Recessed luminaires must be: • IC-rated: IC means “in contact with insulated ceiling” • Labeled: Air leakage rate of ≤ 2.0 cfm Image source: Urban Green Council, “Spending Through the Roof”

• Housing sealed at wall/ceiling with gasket or caulk or foam

C402.5.6 LOADING DOCK WEATHERSEALS Cargo doors and loading dock need a “truck seal.”

SHELTER

DOCK SEALS

Heat transfer through recessed lighting fixtures



C403 BUILDING MECHANICAL SYSTEMS Heating and cooling loads depend upon the characteristics of the building envelope. Designers must calculate these loads and size mechanical systems to match. The code provides minimum requirements for equipment efficiencies, controls, duct insulation, and energy recovery ventilation. This section describes how the code regulates the design and installation of heating and cooling systems.

C403.2 PROVISIONS APPLICABLE TO ALL MECHANICAL SYSTEMS (MANDATORY) The provisions in this section are required and cannot be part of prescriptive or performance tradeoffs.

C403.2.1 CALCULATION OF HEATING AND COOLING LOADS The biggest drivers of heating and cooling loads are:

HEATING

COOLING

• Envelope (windows, walls, roof)

• Envelope (mostly windows)

• Ventilation

• Lights, equipment (plug loads), people, and other internal loads

ASHRAE Standard 183 may already be familiar to mechanical engineers but new to some architects. Heating and cooling load calculations are based on ANSI/ASHRAE/ACCA Standard 183-2007, Peak Cooling and Heating Load Calculations in Buildings Except LowRise Residential Buildings . This standard establishes minimum requirements for building loads that are inclusive of as many procedural methods as possible while identifying core elements that impact heat loss and gains. Standard 183 requires designers to based their heating and cooling calculations on interior design temperatures. Direction on choosing these temperatures can be found in Chapter 3: C302.1 Interior design conditions. • Maximum temperature for heating calculations is 72°F • Minimum temperature for cooling calculations is 75°F Heating and cooling loads must be adjusted to account for load reductions achieved by energy recovery systems.

• Ventilation

COMMUNICATION IS KEY The design and quality of the building envelope determines the load of the HVAC system. Calculate the building’s loads and then size the equipment accordingly. A building with a better designed envelope will have smaller heating and cooling loads which will require smaller systems. In order to accomplish this, a knowledge of envelope systemsand mechanical systems is essential for both the architect and the engineer.

The building on the left has an inefficient envelope and therefore must have a larger heating/ cooling system to compensate.


S M E T S Y S : L A I C R E M M O C

C403.2.2 EQUIPMENT SIZING This size of the proposed heating and cooling equipment must match the calculated load. This means that the selected equipment should be the next available size above the calculated load. This is meant to discourage “rule of thumb” sizing, which makes broad, conservative assumptions that often lead to oversizing. The code says “...A single piece of equipment providing both heating and cooling shall satisfy this provision for one function with the capacity for the other function as small as possible, within available equipment options.” This means the design cannot undersize for either function.

C403.2.3 HVAC EQUIPMENT PERFORMANCE REQUIREMENTS (10 TABLES) Once the heat loads have been calculated and equipment has been sized, you must verify that the selected unit meets the required efficiency at the rated conditions. Make sure you use the correct table for the selected equipment. Mechanical systems are designed for both high and low temperature extremes, which occur only a few hours a year. This means the equipment will function at part load for almost all of its operating life. Note: If the design temperatures are outside of code range and not regulated (i.e. ice storage equipment), the values in the tables need not be followed.

EQUIPMENT SELECTION: AVOID WASTE BY IMPROVING COMMUNICATION Communication is key! Engineers use code minimums as defaults until they receive necessary info (sometimes not until the Design Development phase) Better option:Architect and Engineer communicate early about important envelope issues Added benefit:Smaller equipment, ducts, pipes and fans mean more space for occupants

CODE TABLE ROSETTA STONE Table #

Table Name

Equipment Types Covered

(1)

Electrically Operated Unitary A/Cs DX split systems, RTUs and Condensing Unit (cooling only)

(2)

Electrically Operated Unitary & Applied Heat Pumps

(3)

Electrically Operated Packaged PTACs / PTHPs Terminal Air Conditioners, Packaged Terminal Heat Pumps, Single-Package Vertical Air Conditioners, Single Vertical Heat Pumps, Room Air Conditioners, Room Air-Conditioner Heat Pumps

(4)

Warm-Air Furnaces And Combination Warm-Air Furnaces/ Air-Conditioning Units, Warm-Air Duct Furnaces And Unit Heaters

Furnaces and unit heaters

(5)

Gas- And Oil-Fired Boilers

Gas-fired boiler

(6)

Condensing Units, Electrically Operated

Standalone DX condensing A/C equipment

(7)

Water Chilling Packages

Chiller

(8)

Heat Rejection Equipment

Cooling towers

(9)

Air Conditioners And Condensing Units Serving Computer Rooms

NEW TABLE

(10)

Heat Transfer Equipment

Plate and frame heat exchangers (NEW TABLE)


Split systems, RTUs, Heat pumps


EFFICIENCY RATINGS

Various parameters describe the effectiveness of heating and cooling equipment. Using these terms is the only way to unambiguously ensure that equipment of the highest performance is being used. COP (Coefficient of Performance): the ratio of useful cooling energy removed by a system to the energy that it uses. Specific Power (kW/ton): The ratio of the power input to the compressor in kilowatts to the cooling power under design load in tons. It can also represent the performance of the chiller only, or the chiller with associated pumps—so, confirm before documenting.

=

=

Thermal energy removed (kW) Energy input (kW)

Electricity input (kW) Cooling power (tons of cooling)

EER (Energy Efficiency Ratio): The equipment’s heat movement in Btu/hr divided by the electricity consumed when the unit is operating at 100%, and it includes all auxiliary power draws. EER is measured and averaged over the entire operating season. =

SEER (Seasonal EER): The efficiency of cooling equipment varies with the outdoor temperature. Because the EER is measured at one specific temperature, it does not offer a good prediction of how much electric power will be used over the course of an entire heating season. The SEER measures performance at various temperatures, seasonal performance, and the impact of starting and stopping. Although it is generally a lower number than the EER, it is also a more accurate predictor of performance.

Thermal energy (btu/hr) Electricity input (kW)

ASHRAE Values in ASHRAE vary slightly from those in the IECC NYC NYCECC requires higher efficiencies for some tables

IEER (Integrated EER): Calculated over part load efficiency, this is often u sed for VRF and split systems that do not often use all of their components at the same time.

Fig X.XXX

C403.2.4 HVAC SYSTEM CONTROLS

C403.2.4.1.2 DEADBAND

Controls tell equipment what to do and when to do it.

When controlling heating and cooling in same

The following sections are mandatory.

zone, the thermostat must be capable providing a deadband of 5˚ between heating andofcooling set points—meaning that neither the heating nor cooling system will be used when the interior temperature is within this range.

C403.2.4.1 THERMOSTATIC CONTROLS

Each zone must be individually controlled so that the equipment knows when the space has reached the desired temperature and the equipment can stop delivering heating or cooling.

zzz...

C403.2.4.1.1 HEAT PUMP SUPPLEMENTARY HEAT

Electric heat can run ONLY if the temperature in the space starts to drop while the compressor is running.

<70˚

70˚- 75˚ (Deadband)

>75˚

“Deadband”describes the temperature range when neither the heating nor cooling systems will activate.

C403.2.4.1.3 SET POINT OVERLAP RESTRICTION

A limit switch, either mechanically or digitally controlled is required to maintain the deadband.

C403.2.4.2 OFF-HOUR CONTROLS Automatic controls for systems larger than 6,800 BTU/hr are required to prevent energy waste. The code lists certain required capabilities for thermostats such as 7-day programming and automatic stop, start, and setback. 27 DRAFT FOR REVIEW: NOT PROOFREAD


C403.2.4.3 SHUTOFF DAMPERS The design team must show that motorized exhaust dampers, required at outdoor air intakes, exhaust openings, stairway enclosures, and elevator shaft vents, will be air-tight when closed and have automatic controls to open them only when needed. Gravity dampers are still allowed in buildings less than three stories or where the design exhaust capacity is < 300 cfm. C403.2.4.4 ZONE ISOLATION

Avoid one thermostat being used to control different systems (e.g., master/slave configuration) that will have unique operating loads or hours. HVAC systems serving large zones (25,000 sf or more than one floor) and operated non-simultaneously must be able to be operated independently. C403.2.4.5 SNOW- AND ICE-MELT SYSTEM CONTROLS

To ensure that this energy-consuming system runs only when it’s likely that ice will form and run no longer than necessary, controls must automatically shut off the snow- or ice-melting system when the temperature of the pavement is≥ 50˚ and the outdoor temperature is≥ 40˚. C403.2.4.6 FREEZE PROTECTION SYSTEM CONTROLS

To avoid wasting energy, controls must automatically shut off the freeze protection systems when the outdoor temperature is≥ 40˚. C403.2.4.7 ECONOMIZER FAULT DETECTION AND DIAGNOSTICS (FDD)

Economizers reduce the heating or cooling load by bringing unconditioned outdoor air into the building on mild days. Economizers can be costly additions to a HVAC system and if they are not operating properly, the system will not work as efficiently as designed. Note: Economizers are a prescriptive requirement and there are exceptions to when they must be installed. An FDD system is only required if an economizer is present. See C403.3 for more information on economizers. The code requires sensors that detect the temperatures of the outside air, supply air, and return air to make sure that the economizer is operating when the outdoor temperature is within the specified range.


C403.2.5 HOT WATER BOILER OUTDOOR TEMPERATURE SETBACK CONTROL In a building with one- or two-pipe heating systems, basing the supply water temperature on the outdoor temperature, rather than waiting for the heat to be demanded internally, provides more consistent heating. The code requires that these systems have an outdoor setback control that will lower the water temperature when the weather is warmer.

C403.2.6 VENTILATION The mechanical code requires outside ventilation air for a healthy indoor environment. But ventilation air has an energy cost indoor because it takes energy to bring that air to the desired temperature and humidity levels. The energy code reduces energy cost by limiting the delivery of ventilation air to the minimum amount required by the mechanical code.

C403.2.6.1 DEMAND CONTROLLED VENTILATION Demand Controlled Ventilation (DCV) detects how many people are in a room by measuring the amount of CO2 in the air, and necessary ventilation adjustments to improve air quality. DCV is required if the room is larger than 500 sf AND the anticipated occupant density > 25 people per 1,000 sf as listed in Table 403.3 of the International Mechanical Code (IMC). Note that there are many exceptions to this requirement—the code recognizes the need for a fair return on investment of the more capital-intensive energy saving technologies. C403.2.6.2 ENCLOSED PARKING GARAGE VENTILATION CONTROLS

Previously, garage ventilation fans ran continuously to exhaust carbon monoxide. If the space was heated to prevent freezing pipes, that heat would be lost as it is exhausted from the garage. The code now requires carbon monoxide sensors to control the amount of air exhausted to match the number of active cars in the garage. Note: Although calculated differently, ASHRAE and IECC require ventilation in enclosed garages and achieve similar energy results.


C403.2.7 ENERGY RECOVERY VENTILATION SYSTEMS

C403.2.9 DUCT AND PLENUM INSULATION AND SEALING

Rather than simply exhausting air that the building owner spent money heating or cooling, an Energy Recovery Ventilation System (ERV) recovers the energy in the return air before exhausting it and transfers it to the supply air.

Heating and cooling air costs money and energy. Insulating and air sealing the distribution system will ensure that the air gets delivered where it is intended to go.

In 2009 IECC, the minimum size requirement for an ERV was 5,000 CFM with 70% minimum outside air. In 2012 IECC the minimum size was reduced again, and in 2015 IECC it was reduced even further (as seen in Fig. xx.) An ERV also allows some of the moisture to be transferred from one air stream to the other so code requirements vary for different climate zones based on humidity as shown in Tables C403.2.7(1) and C403.2.7(2). Note that all zones in New York State are labeled ‘A.’ There are exceptions for systems that carry air that contains toxins (paint, lab fumes), air that has grease in it (kitchens, fume hoods), air that is too cold, air that is heated/cooled by renewable energy, or for systems that aren’t used frequently. The code recognizes the tradeoff between energy recovery and demand control ventilation. If your project has a large occupancy, DCV probably makes more sense economically. If the occupancy is low, ERV may be more appropriate. The energy code does not require both.

Supply ducts and return air plenums must be insulated to at least the levels in the residential code. All ducts, including joints, seams, connections, air handlers and filter boxes must be well sealed. Note that there are different requirements for low-, medium-, and high-pressure duct systems. High-pressure ducts (>3 inches) must be leak tested.

C403.2.10 PIPING INSULATION Similar to the requirements for air distribution systems, piping containing heated or cooled liquids (fluids below 60˚ or above 105˚) must be insulated to avoid heat transfer and loss of system efficiency. The required thickness of insulation with specified R-value depends on the pipe size and temperature of the fluid, per Table C403.2.1.

C403.2.11 MECHANICAL SYSTEMS COMMISSIONING AND COMPLETION REQUIREMENTS See C408 for commissioning requirements for: • C403: Building Mechanical Systems

0% ll u

F t e a t a ir R A w r o o fl o r i d t A u n O g i t s n e e c D r e P

10% 20%

• C404: Service Water Heating Additional systems required under 2015 IECC

30% 40%

• C405: Electrical Power and Lighting Systems

C403.2.12 AIR SYSTEM DESIGN

Additional systems required under 2012 IECC

50%

AND CONTROL

60% 70% 80%

Required an ERV under 2009 IECC

90% 100% 5

10

15

20

25

Design Supply Airflow Rate (1000 CFM)

Successive versions of the energy code have required more buildings to have ERVs.

30

Motors that operate below their rated power waste considerable energy. The code is structured to minimize these losses by making it hard to specify oversized fan motors, so this provision establishes a limit on how much power a system moving a specified amount of air at design conditions can use. There is flexibility with respect to how power is divided between different fans in the system, but the total fan power is limited. Systems using less than 5 hp need not comply, and there are other exceptions. For example, compliance is required if:

Supply fan + Return fan + Fan-powered terminal units > 5 HP Note: If the project doesn’t comply with this IECC mandatory requirement, thehas project mustlimits use but are ASHRAE 90.1/2013—which the same prescriptive so trades can be made between systems.



C403.2.13 HEATING OUTSIDEA BUILDING

REFRIGERATION

Exterior heating systems must be radiant systems (i.e., warming by direct line of sight, rather than heating the air itself) and have an occupancy sensing device or a timer switch, so that the system turns off when nobody is present.

In today’s supermarkets, refrigeration typically consumes more than 50% of total electric energy usage. 2015 IECC has new requirements to prevent loss of cooling from refrigeration equipment. • C403.2.14 Refrigeration equipment performance • C403.2.15 Walk-in coolers, walk-in freezers, refrigerated warehouse coolers and refrigerated warehouse freezers • C403.2.16 Walk-in coolers and walk-in freezers • C403.2.17 Refrigerated display cases

C403.3 ECONOMIZERS When the outside temperature is pleasant, economizers supplement conditioned air with outdoor air. Every cooling system that has a fan must have either an air or water economizer. Separate from C403.2, which are all required measures, Economizers are not always cost effective for all systems or climates so the code recognizes exceptions specifically for very efficient systems and systems that are run infrequently. Systems with heat recovery are also exempt. All economizers must have diagnostic controls to ensure they are functioning properly. See section C403.2.4.7 for more information about this requirement. Equipment specifications and exceptions vary greatly depending on the size and complexity of the HVAC system.

An outdoor heating lamp

Outdoor Air

Logic Controller

Temperature Sensor Economizers act as a “switch” to use more outside air or more return air, depending on the temperature outside. In mild the economizer will weather, limit the amount of return air that is recirculated and use more outdoor air. Conversely, during hot or cold weather, the economizer will limit the amount of outdoor air that is used.


Return Air Filter

Supply Air

Heating/Cooling Elements


C404 SERVICE WATER HEATING All of the requirements in this section are newly mandatory in 2015 IECC. Many of the requirements for Mechanical Systems also apply to Service Hot Water, such as • Minimum equipment efficiencies • Pipe insulation • Commissioning

C404.2 SERVICE WATER-HEATING EQUIPMENT PERFORMANCE EFFICIENCY Water heating equipment is subject to minimum efficiency ratings per Table C404.2. Unlike the tables for HVAC equipment, this table uses formulas rather than efficiency ratings. In 2015 IECC, large water heating systems (>1,000,000 btu/h) that service an entire building must have a thermal efficiency ≥ 90%. This can be either a single piece of equipment or several pieces of equipment combined. Practically, this makes condensing equipment almost mandatory for this building class. Note that this requirement does not apply if at least 25% of the building’s hot water needs are provided by a solar thermal system.

C404.3 HEAT T RAPS Heat traps prevent heated water from flowing back into the supply water as a result of convection, and are required on non-circulating systems. A heat trap can be a simple loop of pipe or nipples that only allow water to flow in the desired direction. On circulating systems, heat traps are not required but are good practice to install since they will prevent heat loss when the circulation is turned off at times of low usage, per section C404.6.

C404.4 INSULATION OF PIPING Pipe insulation has one of the fastest paybacks of any high-performance building strategy. Pipe insulation saves energy by preventing heat loss from warm water and from freezing damage in cold weather, but it also protects workers and occupants from unintentional burns from hot pipes.


C404.5 EFFICIENT HEATED WATER SUPPLY PIPING With the conventional trunk-and-branch method, hot water cools in the pipe (even well insulated pipes), and the energy used to heat it is wasted. The energy code reduces this waste by limiting either pipe length or water volume per linear foot of pipe between fixture and source of heated water.

C404.6 HEATED-WATER CIRCULATING AND TEMPERATURE MAINTENANCE SYSTEMS Hot water circulation systems, as seen in figure XXXX, avoid waste of water and heating energy by providing a ready supply of hot water at the fixture, so the occupant doesn’t need to run water until it heats up. However, these systems must have a circulation pump with automatic controls that turn off the pump when water is hot and there is no demand.

C404.7 DEMAND RECIRCULATION CONTROLS A demand recirculation water system is required in projects (typically retrofits) where the recirculation system pumps water from a heated-water supply pipe back to the heated-water source through a cold-water supply pipe, which means that: • The control senses flow of heated water AND • The control limits the water temperature entering the cold-water piping to 104°F.

C404.11 SERVICE WATER-HEATING SYSTEM COMMISSIONING AND COMPLETION REQUIREMENTS See C408 for commissioning requirements for: • C403: Building Mechanical Systems • C404: Service Water Heating • C405: Electrical Power and Lighting Systems


C405 ELECTRICAL POWER AND LIGHTING SYSTEMS Good lighting design is an equal combination of: 1. Efficiency:Use lamps that provide the needed light with the lowest power usage. 2. Application:Use fixtures appropriate for intended use.

Provide appropriate 3. Comfort and aesthetics: light color and color rendering.

LAMP EFFICACY Since we are limited in the amount of power we can use for lighting, it is critical that we use light fixtures that meet the application’s requirements and give the proper light quality with the best efficacy. Lamp efficacy is the effectiveness of a lamp measured in output lumens per input watts.

If occupants don’t have enough light, the fixtures are inappropriate or the color is uncomfortable, occupants and operators will change the lighting over time and reduce the energy savings.

LUMENS The lumen is the basic unit of visible light emitted from a source. There are multiple options to achieve a certain level of lumens. For example, a 100 W incandescent, a 23 W CFL, or a 16 W LED can each emit 1,500 lumens, but the LED’s lamp efficacy of 94 Lumens/Watt far exceeds an incandescent bulb’s efficacy of 15 Lumens/ Watt.

Incandenscent

CFL

LED

1,500 Lumens 100W

1,500 Lumens 23W

1,500 Lumens 16W

Low efficacy

High efficacy Very high efficacy

All of these lamps produce the same amount of light (1,500 lumens), but use a different amount of energy to do so.

RANGE OF MAINTAINED EFFICACY

10 Lumens

350 Lumens

1,500 Lumens

All of these lamps produce a different amount of light, measured in lumens.

Lamp Efficacy (Lumens/Watt) It is important to note that Lumens/Watt should not be the only determining factor in selecting lamps.


L A IC R T C E L E D N A G IN T H IG L : L IA C R E M M O C

C405.1 GENERAL (MANDATORY) Lighting energy is determined by the power running to the lamp and how long that fixture is operating. To reduce lighting energy in a building, the energy code regulates the controls that reduce the time that the lights operate and limits the amount of electrical power allocated to lighting. This can be written as the formula below:

ENERGY CONSUMPTION (kWh) = POWER (kW) x TIME (HOURS) POWER

Can be reduced by lowering lighting wattage

TIME

Can be reduced by lusing lighting controls and sensors

C405.2 LIGHTING CONTROLS (MANDATORY)

DIFFERENCE BETWEEN OCCUPANCY AND VACANCY SENSOR An occupancy sensor turns lights ON automatically when motion is detected and then turns the lights OFF automatically when an area is vacated. A vacancy sensor requires that the user manually activate the light and then turns the lights OFF automatically when an area is vacated. The current NYC Energy Conservation Code (2014 NYCECC) requires vacancy sensors in many spaces where the current Energy Conservation Construction Code of New York State (2012 ECCCNYS) allows occupancy sensors. The new 2016 ECCCNYS based on 2015 IECC catches up to the NYCECC and requires vacancy sensors in most locations

C405.2.2 TIME-SWITCH CONTROLS By having lights illuminated only when needed, and taking advantage of daylight, lighting controls are a crucial first step for reducing lighting energy.

C405.2.1 OCCUPANT SE NSOR CONTROLS Occupant sensor controls are required in most commercial spaces. See code for list of spaces where these are required. The occupancy sensor functionality described in the code is found in controls called “vacancy sensors”. This type of sensor requires: • Automatically turn off lights within 30 minutes of all occupants leaving the space • “Manual on” or automatic on to ≤ 50% power (unless full-on needed for safety reasons) • Must have a “manual off” switch

Areas without occupant sensor controls must have programmable time switch controls. Manual light reduction controls must also be provided in spaces with time-switch controls in order to give the occupant a way to dim the lights by turning off some fixtures or some lamps within each fixture.

C405.2.3 DAYLIGHT-RESPONSIVE CONTROLS Spaces are of daylit and lighting that alsomust havehave more than 150that Watts general daylight responsive controls. This section defines the size and location of daylight zones adjacent to windows (vertical fenestration) and below skylights (toplighting). This section also lays out the dimming and calibration requirements for the controls that respond to daylight. This section is closely connected to the requirements for window-to-wall ratio (C402.4.1 Maximum fenestration area)



DAYLIGHTING ZONES Increasing the size and number of windows increases access to natural light and lowers energy needs for lighting. However, it can potentially increase the need for heating and cooling energy. Good design balances occupant comfort as well as the building’s energy consumption. Being able to find the area of floor space that qualifies as a daylighting zone is important when considering lighting controls and window-to-wall ratio (See section C402.4, Fenestration).

VERTICAL FENESTRATION

SKYLIGHTS

The daylighting zone for vertical fenestration extends into the room to the height of the window, and two feet to either side. Full-height walls will “block” the daylight zone.

The daylighting zone for skylights extends in all directions 0.7x the height of the ceiling. Any obstructions that are taller than 0.7x the height of the ceiling will “block” the daylight zone.

C405.2.3.2(4) SIDELIGHT DAYLIGHT ZONE

E N O Z T H G I L Y A D A T O N

The distance from the fenestration to any building or geological formation which would block access to daylight must be greater than the height from the bottom of the fenestration to the top of the building or geologic formation. C405.2.3.3(2) TOPLIGHT DA YLIGHT ZONE

A skylight must receive direct sunlight when the sun is at peak angle on the summer solstice to qualify as a daylight zone.


PEAK SUN ANGLE AT SUMMER SOLSTICE

SKYLIGHT NOT A DAYLIGHT ZONE


C405.2.4 SPECIFIC APPLICATION CONTROLS Some types of lighting such as under-cabinet lighting, display lighting and grow lights need to be controlled separately from general lighting, but must still be connected to either an occupant sensor or time switch control.

(Labeled wattage of luminaires for

+ SL

Screw-in Lamps) + LV

(Watage of the transformer supplying

Low-Voltagelighting) (Wattage of line-voltageLighting

+ LTPB

Tracks and Plug-in Busways as C405.2.5 EXTERIOR LIGHTING CONTROLS

the spcified wattage of the luminaires) (The wattage of all OTHER luminaires and lighting sources not covered previously)

The energy code requires exterior lighting controls that turn off lighting as function of available daylight and dawn and dusk times.

+ OTHER

Building façade and landscape lighting must have controls for both dawn and dusk and for opening and closing times.

___________________ (Total Connected Lighting = TCLP Power, in Watts)

All other exterior lighting must have controls that reduce their power by at least 30% between midnight and 6:00, one hour before opening and one hour after closing, or any time that the space is unoccupied for more than 15 minutes.

C405.4 INTERIOR LIGHTING POWER REQUIREMENTS (PRESCRIPTIVE)

WHAT IS LIGHTING POWER DENSITY (LPD)? Lighting Power Density is watts of lighting power (as calculated in C405.4.1) divided by the square foot area of the space considered, or:

Watts The project will comply if the total connected interior lighting power is less than or equal to the total allowed interior lighting power.

C405.4.1 TOTAL CONNECTED INTERIOR LIGHTING POWER To calculate the total connected interior lighting power, the designer must use equation 4-9 (see right). The calculation asks for the total lighting wattage proposed on the project: Not all lighting equipment is included in the calculations. There are fifteen exceptions listed in Section C405.4.1.


LPD = Area (ft ) of illuminated space 2

For example:

3,000 ft2 LPD = 320 / 3000

320W

2 = 1.07 W/ft

C405.4.2 INTERIOR LIGHTING POWER The code recognizes that different spaces need different lighting. For example, the code allows much more lighting power density in an operating room than in an office space. There are two pathways to comply with interior lighting power requirements. The first is the Building Area Method, which is determined using Table C405.4.2(1). The second is the Space-by-Space Method, which uses Table C405.4.2(2). C405.4.2.1 BUILDING AREA METHOD

The lighting power allowance is determined by building type. This method is used to estimate overall lighting power for the project. For the Building Area Method, the interior lighting power allowance is the floor area for each building area type listed in Table C405.4.2(1) times the value from Table C405.4.2(1) for that area. C405.4.2.2 SPACE-BY-SPACE METHOD

The lighting power allowance varies by space. This is the method most often used by lighting professionals for compliance because it gives more power where you need it (This method used to be available only in ASHRAE 90.1.). To determine the maximum allowed lighting power on the project, multiply the floor area of each space times the value for the space type in Table C405.4.2(2). The sum of all the spaces equals the Total Allowed Interior Lighting Power (in Watts). This method allows trade-offs between spaces. Note, the designer can use COMcheck to perform this calculation, rather than complete by hand.

Bar and Lounge (LPD: 1.01) Fig X.XXX

Office (LPD: 0.82)

AREA

X

Retail (LPD: 1.26)

LPD

1,000 ft2

1.01

500 ft2

0.82

500 ft2

1.26

= 1,010 W 410 W 630 +W

Total Allowed Interior Lighting Power = 2,050 W


405.4.2.2.1 ADDITIONAL INTERIOR LIGHTING POWER Some additional interior lighting power is allowed in certain retail and sales applications provided the power is used solely for display purposes and is controlled separately from general lighting.

Once you have found theTotal Connection Interior Lighting Power using the equation on the previous page, ensure that it is less than or equal to theTotal Allowed Interior Lighting Power, calculated by either the building area method or the space-by-space method:

C405.4.1 Total Connected Interior Lighting Power SL + LV + LTPB + Other ________ = TCLP

≤

C405.4.2 Total Allowed Interior Lighting Power Building Area Method OR Space-by-Space Method

C405.5 EXTERIOR LIGHTING (MANDATORY) Exterior lighting has its own lighting budget, which cannot be traded with the interior lighting budget. To determine the basic power allowance and LPD for exterior lighting applications, first look at Table C405.5.2 (1). This table describes 4 lighting zones, and the designer must choose the most appropriate zone based upon the building’s location. New York City (and some other municipalities) have pre-mapped lighting zones, meaning that the designer is not allowed to choose which lighting zone the building belongs to.

Once the zone is identified, the designer can calculate the total exterior lighting power based on Table C405.5.2(2). The first half of the table shows tradable surfaces and the second half shows nontradable surfaces. Nontradable surfaces include exterior spaces that need safety and security lighting like ATMs, guarded facilities, or loading areas for law enforcement. Trade-offs are allowed among the tradable surfaces listed. After the total allowed is established, the designer can use more light in one area and less in another as long as the total remains equal to or less than the total. There are numerous exterior lighting exceptions listed in the code.

C405.6 ELECTRICAL ENERGY CONSUMPTION (MANDATORY) Dwelling units in Group R-2 building must be submetered. When occupants are responsible for paying their own electric bill and are aware of how much energy they are using, substantial savings and energy conservation can be achieved.

NEW YORK CITY’S LOCAL LAW 88 Although the energy code only stipulates that R-2 buildings comply with the submetering requirement, New York City’s Local Law 88 requires that all buildings larger than 50,000 ft2 (or two buildings on the same lot totaling 100,000 ft2 ) must submeter tenant spaces. There are some exemptions: • buildings Dwelling units in R-2 or R-3 residential • A-3 residency space in a house of worship • 1 - 3 family homes • Condos and Co-ops with no more than 3 dwelling units


C405.7 ELECTRICAL TRANSFORMERS (MANDATORY) & C405.8 ELECTRICAL MOTORS (MANDATORY) Electric motors and transformers are now required to comply with minimum efficiency requirements for electric transformers. There are 14 exempted transformers. Transformers need to meet minimum efficiency requirements from Table C405.7 and be tested and rated in accordance with the procedure in DOE 10 CFR 432. There are four new tables for electrical motors. The efficiencies need to be tested and rated in accordance with DOE 10 CFR 431.

C405.9 VERTICAL AND HORIZONTAL TRANSPORTATION SYSTEMS AND EQUIPMENT This new section regulates elevators, escalators and moving walks. Luminaires in elevators cannot exceed 35 lumens per watt, and ventilation must be provided if they do not have their own air-conditioning system. The elevator ventilation must have controls that de-energize the fans and lighting system when the elevator is stopped and not in use. Automatic controls shall be configured to reduce speed of escalators and moving walks to a minimum when not conveying passengers. Reversible escalators or those designed for one-way down operation must have a variable frequency regenerative drive that supplies electrical energy to the building electrical system when the escalator is loaded with passengers whose combined weight exceeds 750 pounds.

C406 ADDITIONAL EFFICIENC Y PACKAGE OPTIONS C406.1 REQUIREMENTS IECC requireswith the a design one system, and then comply higherteam levelto ofpick efficiency for that chosen system. Note: 2015 IECC added 3 more options. 1. More Efficient HVAC 2. Reduce LPD by 10%

C406.5 ON-SITE RENEWABLE ENERGY Provide on-site renewable energy equal to: • Minimum 0.50 W/ft2 of conditioned floor area • Minimum 3% of the energy used within the building for building mechanical and service water heating equipment and lighting

3. Enhanced Digital Lighting Control(NEW) O P E A : L A I C R E M M O C

4. On-Site Renewable Energy 5. Dedicated Outdoor AirSystem (NEW) 6. More Efficient SHW (NEW)

C406.2 MORE EFFICIENT HVAC EQUIPMENT PERFORMANCE Select equipment that exceeds the minimum efficiency requirements listed by at least 10%.

C406.3 REDUCED LIGHTING POWER DENSITY Use only 90% of the allowable LPD using either Building Area Method or Space-by-Space Method.

C406.4 ENHANCED DIGITAL LIGHTING CONTROLS 1. Luminaires must be capable of continuous dimming 2. Max. 4 luminaires controlled together individually 3. Max. 8 luminaires controlled together in a daylight zone 4. Digital Control System: Control reconfiguration addressability »

»

Load shedding

Individual user control of overhead general illumination in open offices • Occupancy sensors shall be capable of being reconfigured through the digital control system

»


Fig X.XXX

C406.6 DEDICATED OUTDOOR AIR SYSTEM • 100% outdoor air to each occupied space for multiple-zone HVAC systems • Total energy recovery • Automatic supply-air temperature controls that reset in response to building loads or outdoor air temperatures

C406.7 REDUCED ENERGY USE IN SERVICE WATER HEATING Use the following technologies to provide 60% of hot water (100% if using energy recovery): 1. Waste heat recovery from service hot water, heatrecovery chillers, building equipment, process equipment, or a combined heat and power system 2. Solar water-heating systems Only certain building types that use large amounts of water are eligible, such as dormitories, laundries, health spas and other buildings that show a service hot water load of 10% or more of the total building energy load.

C407 TOTAL BUILDING PERFORMANCE In New York City, the Total Building Performance Path is only available using Section 11 or Appendix G of ASHRAE 90.1-2013.

C407.1 SCOPE This section establishes criteria for compliance using an energy simulation. This energy model includes all energy expected to be consumed in the building including demands from building operation (HVAC systems, service water heating, fan systems, and lighting power) as well as energy related to the building’s use (receptacle and process loads). The energy used by a building using the performance path is generally equivalent to the current prescriptive requirements. The energy used by the building is compared to the baseline. It provides additional flexibility as it allows the design team to use a variety of materials and approaches that may or may not meet prescriptive requirements. A whole-building performance model allows tradeoffs to be made for components that are important to the design but which exceed the prescriptive requirements. In total, these tradeoffs must be as efficient as the standard reference design.

C407.2 MANDATORY REQUIREMENTS In addition to providing a compliant energy model, the building must also comply with all mandatory sections in C402.5, C403.2, C404 and C405.

C407.3 PERFORMANCE-BASED COMPLIANCE Compliance using the performance approach requires a simulation of annual energy cost that sums the energy of a building as it varies every hour over the course of a year. These simulations accounts for climate, occupancy, and building type. In the simulation, a model of the proposed building must have a lower energy cost as compared to an energy cost index (ECI) of a standard reference design. Note that ASHRAE 90.1-2013 requires building energy cost to be even lower—only 85% of the standard reference design building. The parameters of the standard reference design are determined by the rules set forth in this section of the code. Off-site renewable energy is considered the same as any other energy source but on-site renewable energy can be excluded from the simulation.

C407.4 DOCUMENTATION The design professional must submit a compliance report that documents that the proposed design has annual energy costs less than or equal to the standard reference design.

C407.4.1 COMPLIANCE REPORT The compliance documentation should include the following: • Address of the building • An inspection checklist which shows the proposed design as specified in Table C407.5.1(1). The checklist needs to show the estimated annual energy cost for both the proposed design and standard reference design. • report Name of the person completing the compliance • Name and version of the software used


H T A P E C N A M R O F R E P : L A I C R E M M O C

C407.4.2 ADDITIONAL DOCUMENTATION In addition to the documentation outlined above, the code official also has the right to ask for any of the following: • Documentation of the standard reference design building component characteristics • Floor plans of the thermal zoning scheme for both the standard reference design and proposed design • Input and output reports fromthe energy analysis simulation program, along with the files • An explanation of any error or warning messages appearing in the simulation tool output • A certification signed by the builder providing the building component characteristics of the proposed design as given in Table C407.5.1(1)

C407.6 CALCULATION SOFTWARE TOOLS The code includes a comprehensive list of all functions that the software tools must be capable of calculating. The documentation needs to verify the accuracy of the compliance software tool used. Typical tools include eQUEST or EnergyPlus. The designer needs to input the standard reference design using Table C407.5.1(1). Some capabilities include: part load performance curves, hourly variations occupancy, and building operation for a full calendarin year. The code official may also authorize tools for a specified application or limited scope.

C407.5 CALCULATION PROCEDURE The calculation procedure for the proposed design and standard reference design must use identical methods and techniques. The calculation procedure refers to Table C407.5.1(1). • Table C407.5.1(1): Specifications for theStandard Reference and Proposed Designs »

A building modeled in eQUEST

This table lighting, contains heating, most of cooling, the building envelope, and service water heating systems

• Table C407.5.1(2): HVAC Systems Map • Table C407.5.1(3): Specifications forthe Standard Reference Design HVAC System Descriptions • Table C407.5.1(4): Number of chillers • Table C407.5.1(5): Water Chiller Types


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C408 SYSTEM COMMISSIONING Even when equipment is specified and installed correctly, it is still possible that systems will not operate as planned once the building is occupied. A careful process is needed to ensure that different systems do not interfere with each other, and that alltested controls The commissioning process verifies that a facility has been designed, constructed, and to operate perform correctly. as expected. Commissioning is the time in the construction process when the systems are tested in a prescribed manner so any remaining defects are observed and corrected—defects that might otherwise remain hidden well into occupancy. By highlighting these problems during the construction process, their impact is greatly lessened and correction is simplified. Any issues discovered can be corrected before the warranties expire and prior to any damage occurring to connected systems or harm to personnel.

C408.1 GENERAL This section specifically covers system commissioning (Cx) for Building Mechanical Systems (C403) and Electrical Power and Lighting Systems (C405). Although not listed in this provision, Section C404.11Service Water-Heating System Commissioning and Completion Requirements requires commissioning for Service water-heating systems and controls.

WHO PERFORMS COMMISSIONING SERVICES? The 2015 IECC tasks theRegistered Design Professional or Approved Agency(a separate person or organization authorized to make inspections)with providing evidence that systems commissioning was completed properly. The Commissioning Agent, or Commissioning Authority (CxA) is normally an independent third party hired by the Owner. The CxA can be an employee of the design team, the building owner, or the contractor, as long as he or she is not working on the project in another capacity. Rules for who can provide commissioning services are created by each jurisdiction. The CxA is involved in every phase of project development. To ensure that it is done consistently and correctly, the Commissioning Agent (CxA) is responsible for the process from beginning to end.

C408.2 MECHANICAL SYSTEMS AND SERVICE WATER-HEATING SYSTEMS COMMISSIONING AND COMPLETION REQUIREMENTS The commissioning process starts during the design phase. It is mandatory for commercial building systems, with the following exceptions: • Mechanical and service water heater systems are exempt from commissioning if the total mechanical capacity is less than 480,000 Btu/h (140 kW) cooling capacity and 600,000 Btu/h (175.8 kW) combined service water-heating and space heating capacity. • Systems included in C403.3 (Economizers) that serve individual dwelling or sleeping units

C408.2.1 COMMISSIONING PLAN The CxA creates a detailed Cx plan for the Cx process. The plan outlines the key areas of the installation that are inspected and tested when systems become operational, and again when the building is ready for final inspections and occupancy. Cx Plan must include: • Narrative description of Cx activities during each phase, including responsible personnel • List of the specific equipment, appliances& systems to be tested and a description of the tests to be performed. • Functions to be tested including calibrationsand economizer controls. • Conditions under which each test will be performed. • Measurable criteria for performance. • Approved sequence of operations.


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C408.2.2 SYSTEMS ADJUSTING AND

C408.2.5.4 FINAL COMMISSIONING REPORT

BALANCING

A report of test procedures and results identified as “Final Commissioning Report” shall be delivered to the building owner or owner’s authorized agent. The final commissioning reports shall be organized with mechanical and service hot water findings in separate sections to allow for independent review. The final commissioning report includes the results of the functional performance tests as well as the test procedures. If any deficiencies were found during testing, a description needs to be included as well as any corrective measures used or proposed.

The CxA is responsible for providing confirmation that the final air and water flow rates are within tolerances provided in the product specifications. The actual measuring and adjusting of the equipment may be performed by a testing and balancing contractor.

408.2.3 FUNCTIONAL PERFORMANCE TESTING: CONFIRM THAT SYSTEMS WORK AS DESIGNED The Cx process is the first opportunity to test equipment part-load andcan emergency conditions. under Ideally,full-load, the operations team be on hand during the functional testing to observe the tests and “kick the tires.”

C408.3 LIGHTING SYSTEM FUNCTIONAL TESTING

The CxA will confirm that all the controls, components, equipment and systems are calibrated, adjusted and operate properly including sequences of operations. The actual calibration work may be performed by the installers or the controls contractor.

C408.3.1 FUNCTIONAL TESTING: LIGHTING CONTROL SYSTEMS ARE CALIBRATED, ADJUSTED, PROGRAMMED AND IN PROPER WORKING CONDITION

C408.2.4 PRELIMINARY COMMISSIONING REPORT

Lighting control systems are calibrated, adjusted, programmed and in proper working condition. The code has a required list of criteria for controls to meet. For example:

The design professional must provide via the transmittal record, that the Preliminary Cx report, containing tests and results with separate findings for mechanical and service hot water, has been delivered to the Owner. Preliminary report should include: • Any deficiencies that are not yet corrected • Any tests deferred due to weather (and include under what conditions test will be conducted)

C408.2.5 DOCUMENTATION REQUIREMENTS List the following items in the construction documents. These must be provided to the building owner within 90 days of receiving a Certificate of Occupancy.

C408.2.5.1 DRAWINGS • Location and performance data for HVAC and Service Hot Water equipment

C408.2.5.2 MANUALS • O&M manuals • Size and selected options • Calibration information and wiring diagrams • Name and address for at least one service company for each piece of equipment C408.2.5.3 SYSTEM BALANCING REPORT

A written report describing the activities and measurements completed in accordance with Section C408.2.2.


• Are daylighting controlsresponding to daylight properly? • Are time delays for shut-off correct? • Are sensors calibrated so that quiet activities such as typing or reading do trigger the sensors, while false positives such as HVAC cycling, curtain movements, etc do not? • Are all systems “fail-to-on,” sothat if the control breaks, the lights will be on? Egress safety and many codes require it.

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CHAPTER 5 EXISTING BUILDINGS Implementing stricter energy codes on new construction will go a long way to reduce energy consumption in buildings across the state. However, 85% of the buildings that will exist in 2030 already exist and represent a challenge for reducing energy use. The energy code recognizes the difficulties involved with improving the performance of these buildings. The term “existing buildings” refers to buildings constructed before the code’s provisions took effect. The IECC does not require a legally-constructed existing building or system to comply with the current energy code provisions, but does require any new additions and alterations to comply. Note also that the “50% Rule” is no longer in effect—the exemption for commercial renovations, additions, and alterations from being subject to the current state energy code unless the project affected more than half of the building’s systems. Now, any work that is not a repair or maintenance and affects energy use must meet the same requirements as for new construction.

C501 GENERAL

C503 ALTERATIONS

Historic buildingsmay be exempt, however, the design professional or preservation officer must submit a report to show the code offical that compliance would interfere with the historic nature of the building.

Although any alteration must comply, unaltered adjacent building components do not need to be brought up to code.

C503.1 GENERAL

C502 ADDITIONS

There are some exceptions listed in the code:

Additions can comply in two ways: The addition can comply separately, or the addition and existing building can comply as a single building. There are some important issues to pay attention to here: • If the Building Fenestration Area of the addition is greater than 30% WWR and 3% skylights, the addition or the addition + underlying building must comply with daylighting requirements in order to comply. • All mechanical systemsand water heating systems must comply with same provisions as new construction.

• Storm windows installed over existing fenestrations • assemblies Window film installed on existing single-pane • Existing insulation in cavities exposed during construction • Construction where the existing roof, wall, or floor cavity is not exposed • Roof recover and the corresponding air barrier (if no other envelope work is being done) • When less than 50% of the luminaries in a space are being replaced, assuming the installed lighting power doesn’t increase Note that ASHRAE 90.1-2013 is more stringent; if replacing over 10% of the luminaires, it needs to be code compliant.

REPAIRS AND MAI NTENANCE

ALTERATIONS

Don’t need to be brought up to code

Must comply with Code

Unaltered adjacent elements don’t need to comply Fig X.XXX


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IECC RESIDENTIAL PROVISIONS Page 46

R401 General

48

R402 Building Thermal Envelope

58

R403 Systems

61

R404 Electrical Power and Lighting Systems

62

R405 Simulated Performance Alternative

64

R406 Energy Rating Index

65

R501 Existing Buildings


L A I T N E D I S E R

INTRODUCTION The provisions of the International Energy Conservation Code (IECC) promote the effective use of energy in buildings. Conquer the Code teaches design professionals the structure and rationale behind the energy code in order to maximize compliance, as well as the code’s effectiveness. There are several important new provisions in 2015 IECC. As the code strengthens energy requirements for thermal and air barriers and window construction, any new construction or existing building renovation will be better sealed and insulated, thus energy to heat and them.as The residential energyventilation code nowinrequires blower door test toreducing verify thethe strict new required air infiltration limit ofcool 3ACH50, well as mechanical all new a and renovated homes. Additionally, IECC now includes a compliance path known as the Energy Rating Index (ERI), which means that a Home Energy Rating System rating (HERS)—an industry standard that measures a home’s energy efficiency—can satisfy energy code compliance if the home meets a minimum rating. The Residential section of the energy code has three options for compliance. A designer may select either a straightforward “checklist-style” prescriptive path with or without envelope tradeoffs, or a building performance path, which requires an energy model. The flexibility within the code’s performance path requirements encourages the improvement of energy-conserving construction practices, equipment, materials, and techniques. Regardless of which compliance pathway you choose, every project must meet specific mandatory requirements in accordance with 2015 IECC, which cannot be traded off. This course includes all of the mandatory provisions.


A single-family suburban home


R401 GENERAL R401.1 SCOPE All residential buildings must comply with the Residential provisions of the Energy Code. The mechanical systems in multifamily buildings may require the commercial code if the units are served by the same system. Every other type of building uses the commercial code.

COMMERCIAL VERSUS RESIDENTIAL BUILDINGS Residential buildings include: Detached 1- and 2-family dwellings, Multiple single-family dwellings (townhouses), and above Group grade. R-2, R-3 and R-4 three stories or less Any building four stories or more—including multifamily residential buildings—must comply with the commercial code.

Residential

Commercial Commercial

Commercial

Commercial If filing for a building with both residential and commercial, it would all be included in one application and the designer would include two sets of data. One would cover the residential portions, and the other would cover the commercial. This is only necessary if the building is three stories or less and includes commercial and residential dwelling units.

DOES THE PROJECT NEED TO COMPLY WITH THE ENERGY CODE? Few buildings are exempt from the code. Designated historic buildings may be exempt if the design professional or preservation officer submits a report to the code official showing that compliance would interfere with the historic nature of the building (R501.6). Envelope requirements in some very low energy buildings, such as storage sheds, may be exempt. Some renovation projects may be exempt if they do not affect the energy use of the building. Please note, documentation that the building is exempt must still be submitted to the code official.



R401.2 COMPLIANCE PATHS When following the residential energy code, a designer must first choose from one of three compliance paths: prescriptive, performance, or energy rating index (ERI).

PRESCRIPTIVE PATH (“CHECKLIST”) Sections R401 through R404 constitute the prescriptive path. In order to comply with code, this series of prescriptive provisions must be met. For example, the envelope must meet or exceed minimum R-values for walls, ceilings, and other envelope components. For compliance, the design team must show that the HVAC equipment is sized to meet heating and cooling loads and that it meets minimum federally-mandated efficiency. The prescriptive path is often the simplest approach and is fairly easy to use—you can even use a simple spreadsheet as a compliance tool. However, this path is somewhat restrictive as there is little flexibility. If you want to trade off envelope efficiencies, you may comply using REScheck or your own calculation tables.

WHICH APPROACH IS THE BEST FOR THE PROJECT? The “best” approach varies for each project. The prescriptive approach is simple but may be too restrictive. Additions and alterations may best be handled with the prescriptive approach. Complex buildings with non-conforming specialty components, such as large expanses of glazing, may best be handled with the performance approach, that allows tradeoffs between systems in order to deliver an efficient building, despite having some inefficient individual components. Different approaches may produce different results, but the code is designed to produce generally equivalent results. The prescriptive approach is often conservative and does not account for many features that affect energy use, such as external shading.

PERFORMANCE PATH (“ENERGY BUDGET”) Section R405—along with the provisions in R401 R404 that are mandatory for all projects—details the performance path. Design teams that choose this method must provide an energy model in order to demonstrate that the building’s energy use will not exceed the maximum allowed. The performance path allows greater design flexibility and tradeoffs among systems. This compliance path may require more expense and effort if the firm is not used to creating energy models. • Create an energy modelto compare a proposed design to a baseline or reference design. Demonstrate that the design is at least as efficient as the baseline in terms of annual energy use. must be less than or equal • Building Energy Cost to standard reference design building. • Comply using REM/Ratesoftware or approved equivalent.

R401.3 CERTIFICATE In residential buildings, it is a mandatory requirement to post a permanent certificate on the wall of the furnace or utility room. This certificate must include: • R-values of insulation installed on the ceiling/roof, walls, foundation, and ducts outside conditioned space • U-factors for fenestration and the solar heat gain coefficient (SHGC) of fenestration • Results of any required duct system and building envelope air leakage testing done on the building • Types and efficiences of heating, cooling, and service water heating equipment • If a gas-fired unvented room heater, electric furnace, or baseboard electric heaters are installed in the building (These do not need efficiencies listed.)

ENERGY RATING INDEX (“HERS INDEX”) The energy rating index (ERI) approach is explained in depth in Section R406. ERI is a numerical score where 100 is equivalent to a standard 2006 IECC-compliant building and 0 is equivalent to a net-zero home. The current HERS (Home Energy Rating System) rating is compatible with the ERI requirements in the proposal so a builder could use a HERS rating to comply using the ERI path. In New York State, a score of 55 or below is required for climate zone 5; 54 and below for climate zones 4 and 6.

An example certificate



R402 BUILDING THERMAL ENVELOPE The building envelope is the physical barrier between the building’s conditioned interior environment and the outside. Efficient building envelopes prevent air leakage and moisture migration, heat gain and loss, and solar heat gain through windows and skylights. To create a comfortable indoor environment and minimize wasted energy, the energy code requires continuous air barriers, continuous insulation, and efficient windows. The following sections will explain the context behind each code provision and provide examples of how to comply.

R103.2.1 IDENTIFYING THERMAL ENVELOPE THE BUILDING The code provides the following definition of the thermal envelope: The basement walls, exterior walls, floor, roof and any other building elements that enclose conditioned space or provide a boundary between conditioned space and exempt or unconditioned space—basically, the roof, the walls, and the floor. It may seem obvious, but to confirm to the code officials that the building thermal envelope is continuous, it must be possible to draw the building thermal envelope on the construction drawings, without picking up the pencil. (see R103.2.1 Building thermal envelope depiction). In high efficiency buildings, the thermal boundary (continuous insulation) is fully aligned with the air barrier (continuous air sealing).

E P O L E V N E : L IA T N E ID S E R

Knee Wall Ceiling Window Rim Joist

Above-Grade Wall

Basement Wall

The building thermal envelope


Slab-on-Grade

THERMAL BRIDGING Thermal bridging occurs when a poorly insulating material allows heat flow across a thermal barrier. To prevent thermal bridging you must provide a thermal break, such as with continuous insulation, seen in the illustration to the right

Thermal modeling demonstrates how heat transfers through a thermal bridge (left) and how effective construction mitigates heat loss.

— Wall studs are a common point of thermal bridging wood and metal conduct heat more readily than the cavity insulation surrounding them.

R-VALUES AND U-FACTORS

Gysum Board

R-0.64

Cavity Batt InsulationR-13.60 Exterior Sheathing

R-0.62

Vapor Retarder

R-0.06

Continuous InsulationR-5.00 Wood Siding

Total: U-value = 1 / 25.72 =

R-0.80

R 20.72 0.048

The R-value is the capacity of a material to resist

E P

heat flow.there A higher R-value is preferable because it means is a higher capacity to resist heat flow. Much like layering clothes and a coat in winter to prevent heat loss from your body, you can add the R-values of separate elements to get a higher level of insulation.

O L E V N E : L IA T N E ID S E R

The total heat transfer must take two factors into account. The first is the total R value—the capacity of an assembly to resist heat flow based on the sum total of its layers. The R-value of a wall cavity is obtained by adding up the values of its individual parts, as seen in the illustration. The second is the U factor—the simultaneous heat transfer through various types of assemblies that make up the building envelope. The U factor can be found by taking the inverse of the total R value. Unlike R-values, you cannot add U-factors.

R-Values can be found by adding the values of each wall component. To find the U-factor, take the inverse of the total R-value.

R = 1/U


U = 1/R

R402.1 GENERAL (PRESCRIPTIVE) R402.1.1 VAPOR RETARDER

FENESTRATION U-FACTOR

A vapor retarder is a material that reduces vapor diffusion. Expert advice on vapor retarders has changed over the last 30 years, leading to some confusion in the industry as to when and where to install a vapor retarder. If installing a vapor retarder is not already part of your practice, it is recommended that you do some research because improper installation can trap moisture and cause mold growth. The energy code defers to the vapor retarder requirements of Section R702.7 of the International Residential Code or Section 1405.3 of the International Building Code, as applicable.

Low U-factors have a relatively high resistance to heat flow and a strong insulating value, which means that the window assembly is fairly efficient. Types of windows that comply have low-E double- or triple-paned glass filled with an inert gas. Double paned windows that don’t have gas fill or low-E coatings no longer comply.

WOOD FRAME WALLS The R-value column in Table R402.1.2 lists two values for wood frame walls. The first value represents the R-value of the cavity insulation, the second value represents the R-value of the continuous insulation, so “13+5” means

There are many materials available to use as a vapor retarder. Classes are arranged by levels of permeability. • Class Ivapor barriers are the least permeable. These include glass, sheet metal, aluminum foil, and polyethylene.

R-13 cavity insulation plus R-5 continuous insulation (ci).

MASS WALLS The R-value column in Table R402.1.2 lists two values for mass walls. Mass walls relieve you of some insulation requirements. Use the first number if over 50% of the insulation is on the outside of the wall , and the second number if over 50% of the insulation is on theinside. Note that interior insulation on a mass wall is greater than exterior insulation.

• Class IIvapor retarders have a perm rating of 0.1 perm to 1.0 perm. These materials allow more vapor diffusion than Class I and include unfaced expanded or extruded polystyrene, 30 pound asphalt coated paper, plywood, bitumen coated kraft paper, kraft-faced fiberglass batt, and low perm paint.

BASEMENTS AND CRAWL SPACE WALLS The code allows two different ways to comply with the required insulation R-Value.

• Class IIIvapor retarders are semi-permeable and have a perm rating of 1.0 perm to 10 perm. Materials include latex paint and kraft paper.

• Install continuous insulation (ci) at an R-value matching the first number. • Install cavity insulation at an R-value matching the second number .

R402.1.2 INSULATION AND FENESTRATION REQUIREMENTS Table R402.1.2 is an important table that provides prescriptive R-values and U-factors. Pay close attention to the footnotes, as they will explain the various values in the table and exceptions.

Permeability Rating

Also, don’t forget to check the footnotes for some

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allowable substitutions.


Vapor Barrier Vapor Retarder Semi-Permeable Permeable (Class I) (Class II) (Class III) 0.01

0.1

1

10

100

Polyethylene

Asphalt-Coated Kraft Paper

Plywood

Gypsum Board + Primer, Paint Gypsum Board + Primer

Tyvek

Gypsum Board Alone


This chart shows the permeability of various commonly-used materials

The code provides 3 pathways to show compliance:

R402.1.5 TOTAL UA ALTERNATIVE

R402.1.3 R-VALUE COMPUTATION

The Total UA alternative can be found by calculating the sum of the U-factor for each component multiplied by the combined area of that component.

To calculate the R-Value of blown-in insulation (whether it’s cellulose, fiberglass, mineral, rock wool etc…), you must use the “settled R-value.” These types of materials compress under their own weight after installation and get a little denser, so they have less available air to provide insulation. In order to prove compliance you will need to show: installation thickness marker with 1” high numbers that 2 faces the attic access door (at least one per 300ft ), the label(s) from the insulation product, R-Value calculations, and photos of installation.

This is different from the U-factor alternative. The U-factor alternative method is applied to one component at a time—either walls, ceilings, floors, etc. The total UA alternative is applied to the whole building and allows tradeoffs between envelope components including windows and skylights. You can comply by using REScheck or you can do the calculations yourself with a spreadsheet. Total UA = sum of U-factor × assembly area

If the total building thermal envelope UA is less than or equal to the total UA resulting from using the U-factors in Table 402.1.4, then the building complies. This allows envelope components to be traded off against each other.

An installation marker


R402.1.4 U-FACTOR ALTERNATIVE You may reference Table R402.1.4 when trading off envelope components. The U-factors in Table R402.1.4 include thermal transmittance of the entire assembly in addition to insulation: thermal bridging at the studs, the sheetrock, sheathing, siding, etc. The benefit of Equivalent U-Factors is that you can include construction materials that contribute to the insulation value of the assembly, such as interior and exterior air films, so you get more wiggle room than using the purely prescriptive approach. The calculation is not difficult and you can use a simple spreadsheet. To begin the calculation, add all of the R-values and calculate a total R-value for the assembly. To calculate the equivalent U-factor divide 1 by the total R-value: 1/R. Compare your U-factor with the U-factor in Table R402.1.4 to ensure that the assembly is compliant.


UA Alternative can be calculated by hand. However, it is much easier to use software such as RES check.

R402.2 SPECIFIC INSULATION REQUIREMENTS There are additional in sulation requirements not listed in Table R402.1.2. The following section covers additional prescriptive requirements.

R402.2.1 CEILINGS WITH ATTIC SPACES Ceilings with attic spaces can comply in two ways. The first is to follow the requirements in R402.1.2, which requires an R-Value of 49. Alternately, R-38 is permissable as long as it extends over the wall top plate at the eaves. Note that this reduction cannot be used if using the U-factor alternative or the total UA alternative.

Possibility of ice dam formations

Heat loss Insulation (R-49)

Cold corners contribute to condensation and mold growth in some locations

Insulation (R-38)

Insulation at full thickness over exterior walls

An “energy truss” can prevent cold corners by allowing the ceiling insulation to overlap with the wall insulation

R402.2.3 EAVE BAFFLE

R402.2.4 ACCESS HATCHES AND DOORS

Install eave baffles so the insulation does not block the vents (especially important with blown-in insulation).

Attic hatches must have the same amount of insulation as the rest of the attic, and they must be air sealed. E P O L E V N E : L IA T N E ID S E R

Eave baffle with protective chutes to allow ventilation from the soffits


An insulated seal for the attic hatch

R402.2.6 STEEL-FRAME CEILINGS, WALLS AND FLOORS Steel frame structures need higher insulation levels because they have more opportunity for thermal bridging. Table R402.2.6 provides insulation R-values for steel-frame buildings, or use Table R402.1.4 for U-factor requirements.

R402.2.8 FLOORS The code requires that insulation maintain permanent contact with the underside of the floor. If the ceiling were removed the insulation would remain intact.

R402.2.10 SLAB-ON-GRADE FLOORS In climate zones 4 and 5, install minimum R-10 insulation to a depth of 2 feet. It can be installed vertically or turned under the slab horizontally. In climate zone 6, insulate to a depth of 4 feet. The depth is always measured from the top of the foundation wall and should be installed between the slab and the footing. The insulation needs to cover the slab edge to stop a thermal bridging path. The U.S. Department of Energy estimates that slab edge insulation can reduce winter heating bills by 10% to 20%.

R402.2.11 CRAWL SPACE WALLS Wood subfloor Cavity insulation

Code allows you to either insulate the floor above the crawl space OR seal and insulate the crawlspace walls, and put down a vapor barrier over the earth. Many building experts recommend against crawl spaces because they have the water problems of a basement with almost none of the storage space, at much higher cost than a slab. If you need a crawl space, the best practice is to insulate and seal it. Crawl space walls should be insulated with rigid foam or closed-cell spray polyurethane foam, and they should be sealed rather than vented.

Sheathing

EXCEPTION:If the floor cavity insulation goes from top to bottom on the perimeter near the walls, the insulation is permitted to rest on the sheathing.

Crawl spaces should be treated as if they are miniature basements, which is exactly what they are. The best practice is to make a crawl space a conditioned area like the rest of the house. This is permitted by newer versions most building codes, and is much better for the houseofand residents. Unvented crawlspaces are better than insulating the floor above because:

Air gap

• • • • • •

Warmer floor temperature in winter Lower humidity in the crawlspace Lower energy losses Lower risk of freezing pipes Lower distribution losses in the crawlspace Lower risk of animals entering the crawlspace

R402.2.12 MASONRY VENEER

Entire floor cavity by perimeter walls is filled

R402.2.9 BASEMENT WALLS Walls 50% or more below grade and enclosing conditioned space are considered basement walls. You must insulate to 10’ below grade or the basement floor (whichever is less).


Prescriptive requirements specifically state that insulation is not required on the horizontal portion of the foundation that supports a masonry veneer because: •

The veneer is outside the thermal envelope.

•

It is a difficult aesthetic detail to have insulation between lip of foundation wall and brick veneer.


R402.3 FENESTRATION (PRESCRIPTIVE) Fenestration refers to the design and disposition of windows and other exterior openings of a building. Though daylighting is a valuable resource when welldesigned, windows always come at a cost to the efficiency of the building envelope. Efficient windows, the orientation of windows, and the area of fenestration compared to opaque area greatly influence the energy use of the building. The following section covers fenestration requirements provided by the code.

R402.3.1 U-FACTOR Don’t confuse the area weighted U-factor with the Total UA alternative. They are two different calculations and this provision is only for fenestration, not the entire component such as a wall or ceiling. R402.3.1 is more strict because it requires a fenestration U-factor of 0.35, while the Total UA alternative allows 0.48 for average fenestration. This is a useful provision if using a small amount of inefficient glazing and still want to use the prescriptive path, as long as the averages meet the U-factor requirements.

Ty p e o f Wi n d ow Double Pane Low-E

Single Pane Stained Glass

U - f a c to r

A re a

0.3

300

90

1.1

20

22

U *A

R402.3.3 GLAZED FENESTRATION EXEMPTION The code allows a small amount of single-paned glass. Each project is allowed 15ft2 of glass that does not need to comply with fenestration requirements. If you want something small and decorative that is singlepaned such as stained glass you can use this exemption. Up to 15 ft2 of glass doesn’t need to comply

R402.3.4 OPAQUE DOOR EXEMPTION Each project is allowed one side-hinged door of 24ft2 of opaque glass that does not need to comply with fenestration requirements.

We i g h ted U

E P Opaque glass door

Total

320

112

0.35

R402.3.5 SUNROOM FENESTRATION To calculate the area-weighted U-factor, multiply the area of each window (rough opening) by its U-factor. Add up the total UAs, and the total areas then divide the two sums as shown below.


If the sunroom encloses conditioned space, it must meet the fenestration requirements. Windows in sunrooms cannot exceed U-0.45, and skylights cannot exceed U-0.70.

A sunroom


R402.4 AIR LEAKAGE (MANDATORY) The following section will discuss specific regulations to limit air leakage. This entire section is mandatory. For compliance, air sealing details for each component must be shown on your drawings. Also note that the air barrier must align with thermal barrier.

RIM JOISTS Air seal at all vertical and horizontal joints along beams and rim joist.

R402.4.1 BUILDING THERMAL ENVELOPE Because materials expand and contract due to changes in temperature, the code specifies that air sealing materials need to take into consideration the space that will open up between dissimilar materials.

TABLE R402.4.1.1 AIR BARRIER AND INSULATION INSTALLATION This table provides criteria for air barrier and insulation installation details, along with a comprehensive list of 15 locations where air sealing is required. Included with the 15 specific locations there are general requirements as well. Note that air-permeable insulation does not count as a sealing material.

GENERAL REQUIREMENTS •

Install a continuous air barrier which is aligned with the thermal envelope.

•

Seal all breaks or joints.

•

The code lists many common building materials.

Air sealing rim joists

SHAFTS, PENETRATIONS Seal duct shafts, utility penetrations, and flue shafts opening to exterior or unconditioned space. RECESSED LIGHTING Historically, recessed light fixtures have been a source of significant energy loss because they penetrate the building thermal envelope. The code specifies that recessed lighting must be airtight and IC rated. IC-rated: IC means “in contact with insulated ceiling.”

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ICAT-rated recessed lighting fixture

SHOWER/TUB ON EXTERIOR WALL The side of the tub should never be used as a wall—first build the wall and then put the tub in. The walls should be sealed before the tub is installed.

Air sealing the seams of the exterior walls



AIR LEAKAGE: TESTING R402.4.1.2 TESTING Because air sealing is of paramount importance to a home’s energy use, the code now requires air barrier testing to confirm the tightness of the envelope. To measure how much air is flowing in and out of the building, a blower door test is used. A blower door, simply put, is a powerful fan which is placed into the frame of an exterior door. The fan pulls the air out of the house, depressurizing the house to 50 Pa. The negative pressure allows the fan to pull air into the building through infiltration. The airflow, measured at the fan, represents how much outside air is entering the house through infiltration. Thisatairflow cannot exceed 3ACH50 (3 air changes per hour 50 Pascal), which is the code maximum for air infiltration in Climate Zones 3 through 8. Blower door tests are also required for multifamily units. Before you conduct the test, all penetrations in the building envelope need to be complete. All exterior windows and door must be closed and HVAC systems turned off. Open only one exterior door and place the canvas and fan into the door frame. The fan can then begin to depressurize the house and determine the airflow measurement. The infiltration rate must be included in a written report for the code official. If the infiltration rate exceeds 3ACH50, then you will be required to reseal the building until the envelope passes the air leakage test.

Design professional using a smoke test to visualize air leakage at a door sill during a blower door test.

R402.4.2 FIREPLACES New wood-burning fireplaces must have tight fitting flue dampers or doors and a source of outside combustion air.

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R402.4.3 FENESTRATION AIR LEAKAGE Windows are a huge potential source of air leakage so, to help meet strict air tightness requirements, the code provides maximum air leakage rates for fenestration. The air infiltration rate is easily found on the NFRC label (National Fenestration Rating Council). A blower door

AIR BARRIER TESTING— A DIAGNOSTIC TOOL Design professionals can also use blower doors as an opportunity to test the work in progress. The best time to test new construction is after the home is insulated but before the drywall is hung. If the test reveals any problems, they will be easier to fix at this point rather than later. Air barrier testing is a useful tool to ensure that the finished building doesn’t fail inspection. Combining a smoke testthe with a blower door can (as identify areas of leakage during construction process shown above right). Fig X.XXX



R402.4.4 ROO MS CONTAINING FUEL-BURNING APPLIANCES In spaces with open combustion fuel burning appliances that get combustion air from the space: 1.

Appliances and combustion air opening must be located outside the building thermal envelope

OR 2.

R402.4.5 RECESSED LIGHTING Recessed lighting is notorious for poor energy performance. Therefore, the code requires that recessed luminaires need to be sealed to limit air leakage. Recessed fixtures can be sealed with a gasket or caulk between the housing and the ceiling or interior wall. Recessed luminaires need to be IC-rated and have an air leakage rate no greater than 2.0 cfm.

Insulating a recessed light

Enclosed in a room isolated from the thermal envelope with walls, floors and ceilings≥ R-value required at basement walls and Ducts insulated to > R-8 when passing through conditioned space


Best practice: Use sealed combustion units

R402.5 MAXIMUM FENESTRATION U-FACTOR AND SHGC (MANDATORY) The code maximizes window efficiency in all buildings by limiting fenestration air leakage and providing a maximum fenestration U-factor and SHGC. This is mandatory regardless of which compliance path you choose. However, if using either of the “tradeoff” methods for the envelope design—the UA or performance options—there is some flexibility as long as the envelope performs as required with the selected components. Construct the home with windows that have area weighted average U-factor and SHGC values less than or equal to the values for the climate zone and meet the code maximum air leakage requirements.


R403 SYSTEMS Mechanical systems are essential to providing a R403.2 HOT WATER BOILER comfortable environment for the occupant. Since the thermal envelope is to be completely sealed, uncontrolled OUTDOOR TEMPERATURE infiltration can no longer be counted on to circulate fresh SETBACK air into the home. Mechanical systems are now required to provide and distribute the proper amount of fresh air, Using a setback control can save a huge amount of heating, and cooling into the building. The code covers pipes, ductwork, and equipment, and the proper sizing of energy. the mechanical systems. To maximize energy efficiency, mechanical systems must be sized correctly. Before, architects could estimate the size of heating and cooling equipment, and they usually fell back on oversizing equipment. The code requires that systems be designed with the help of two guides from the Air Conditioning Contractors of America: Manuals J and S. They cover heating and cooling loads, system size, and duct design. Systems that are designed with these calculations in mind will run more efficiently and save energy.

R403.3 DUCTS R403.3.1 INSULATION Insulating ducts prevents heat loss as the air is moved around the house. Code requires R-8 if duct is greater than 3” in diameter and R-6 if duct is less than 3” in diameter. Ducts in a conditioned space do not need to be insulated. A conditioned spaceis any room or space enclosed in the thermal envelope that is directly or indirectly heated or cooled.

R403.1 CONTROLS (MANDATORY) Building controls reduce the amount of energy used by the home and can reduce the cost of heating and cooling. The code requires at least one programmable thermostat for each separate heating and cooling system.

R403.1.1 PROGRAMMABLE THERMOSTAT Programmable thermostats need setbacks capable of cooling down to 55˚F and heating up to 85˚F. There must be at least one programmable thermostat in the largest room in the building. It is best practice to have more than one programmable thermostat.

R403.1.2 HEAT PUMP SUPPLEMENTARY HEAT

Ductwork which falls on the outside of the thermal envelope must be insulated.

A heat pump is an electronic device that efficiently heats and cools buildings. Heat pumps tend to be used in high performance buildings because they work well with solar-powered systems. This requirement means that if the heat pump is running and the temperature drops, it is permissible for the electric resistant heat to kick in. However, if the heat pump has turned off because it has reached the necessary temperature and still has capacity to provide more heat, electrical resistance heating is not allowed to come on.

Ductwork on the inside of the thermal envelope does not need to be insulated.


S M E T S Y S : L IA T N E ID S E R

R403.3.2 SEALING

R403.3.5 BUILDING CAVITIES (MANDATORY)

To minimize heat gains and losses, ducts must have all joints and transitions sealed. Properly sealed duct systems can save energy, improve occupant comfort, and increase the life of heating and cooling systems.

Seal collars and stackheads

Seal perimeter of register

This section of the code fixes a historic problem of using building framing for air circulation. It is inefficient to use a building plenum to circulate air because the cavity cannot be sealed. You must use ducts to circulate air within the building. Not only is this better for energy use, but it reduces the contaminants in the area that are picked up from building cavities.

Seal elbows

Seal joints and connections

Seal boots

Seal plenum

Furnace Locations for duct sealing

Floor and wall cavities without ductwork are not suitable for air conduits

R403.4 MECHANICAL SYSTEM PIPING INSULATION (MANDATORY) Insulate the pipes to a minimum R-3 and protect exterior piping from the weather.

R403.3.3 DUCT TESTING

R403.5 SERVICE HOT WATER Duct tightness mustthe be post verified. The codetest, allows two testing options: construction andfor the rough-in test. However, a duct tightness test is not required if the air handler and all ducts are located within conditioned space. A written report of the results must be given to the code official.

R403.3.4 DUCT LEAKAGE Total allowable duct leakage is as follows: During Construction Test • With air handler installed: Max. 4 cfm/100 sf occupied space • Without air handler installed: Max. 3 cfm/100 sf occupied space Post Construction Test: • Max. 4 cfm/100 sf occupied space

SYSTEMS R403.5.1.1 CIRCULATION SYSTEMS Hot water recirculation is a common practice in commercial construction and is typically seen in hotel and apartment buildings. A small amount of water is circulated from the farthest hot water load back to the water heater so that hot water is available immediately. Circulating systems must be pumped, no thermosyphon systems are allowed (passive heat exchange based on natural convection), and controls must be based on both temperature (no higher than 104 F) AND demand (motion sensor or flow sensor).

R403.5.3 HOT WATER PIPE INSULATION Insulate pipes to a minimum of R-3.



R403.6 MECHANICAL VENTILATION (MANDATORY) As mentioned in the beginning of this chapter, buildings must be mechanically ventilated per International Residential Code (IRC) or the International Mechanical Code (IMC). Outdoor air intakes and exhausts need to use automatic or gravity dampers that close when the ventilation system is not operating. This is important because the house can no longer depend on air leakage in the envelope to supply fresh air. Using a gasketed, motor-driven damper which is interlocked with the

R403.8 SYSTEMS SERVING MULTIPLE DWELLING UNITS (MANDATORY) Residential buildings should follow the commercial code requirements for HVAC if it contains systems that serve three or more dwelling units. Section R403.8 states that these buildings should comply with Sections C403 and C404 instead. This must be done if multiple dwelling units are being served by the same system. If there is one system per unit, the system will stay within the residential code.

fan ensures that than the damper staysfan closed even when pressures other the exhaust are placed upon it (for example, stack effect). The gasketing minimizes leakage in either direction and is a best practice for mechanical ventilation.

R403.7 EQUIPMENT SIZING AND EFFICIENCY RATING (MANDATORY) Equipment sizing is an important provision because equipment can no longer be oversized. For compliance, deliver documentation using ACCA Manual J for the load, and Manual S for the sizing.

COMMUNICATION IS KEY The design and quality of the building envelope determines the load of the HVAC system.

Calculate the building’s loads and then size the equipment accordingly. A building with a better designed envelope will have smaller heating and cooling loads which will require smaller systems. In order to accomplish this, a knowledge of envelope systemsand mechanical systems is essential for both the architect and the engineer.

The building on the left has an inefficient envelope and therefore must have a larger heating/ cooling system to compensate.



R404 ELECTRICAL POWER AND LIGHTING SYSTEMS In contrast with the commercial code, lighting systems in residential buildings have very few requirements. The simply code does specify how much lighting to install, but how not much of it needs to meet minimum efficiency requirements.

R404.1 LIGHTING EQUIPMENT (MANDATORY) The code requires a minimum of 75% of lamps in permanently installed lighting fixtures to be highefficacy, or 75% of fixtures need to have high-efficacy lamps.

LIGHTING EFFICACY A lamp’s efficacy is analogous to how efficient it is. A high-efficacy lamp will use a small amount of power (Watts) to produce a large amount of light (Lumens). Lamp efficacy is measured by Lumens/Watt. Therefore, an incandescent lamp that uses 100W to produce 1,500 Lumens would be considered very low efficacy and an

10 Lumens

350 Lumens

1,500 Lumens

All of these lamps produce a different amount of light, measured in lumens.

R404.1.1 LIGHTING EQUIPMENT (MANDATORY) Don’t use continually burning pilot light for lighting systems fueled by gas.

LED that 16W tovery produce the same 1,500 Lumens would be used considered high efficacy.

WATTAGE VS EFFICACY

CODE REQUIREMENTS

All three of these bulbs produce the same amount of light (1,500 lumens). However, the amount of power they draw is drastically different.

2015 IECC defines “high efficacy” lighting as follows:

Lumens/Watts

100W Incandescent

Efficacy LAMPS OVER 40 WATTS:

1500 / 100 =

15 Lumens/ Watt

LOW EFFICACY

1500 / 33 =

45 Lumens/ Watt

HIGH EFFICACY

1500 / 16 =

94 Lumens/ Watt

VERY HIGH EFFICACY

1,500 Lumens

LAMPS 16 - 40 WATTS:

23W CFL 1,500 Lumens

50 Lumens / W

LAMPS 15 WATTS OR LESS:

16W LED

60 Lumens / W

1,500 Lumens


40 Lumens / W

G N I T H G I L : L IA T N E D I S E R

R405 SIMULATED PERFORMANCE ALTERNATIVE R405.1 SCOPE This section establishes criteria for compliance using an energy simulation. This energy model includes all energy expected to be consumed by heating, cooling, and service water heating. The energy used by a building using the performance path is generally equivalent to the current prescriptive requirements. The energy used by the building is compared to the baseline. It also provides additional flexibility as it allows the design team to use a variety of materials and approaches that may or may not meet prescriptive requirements. A whole-building performance model allows tradeoffs to be made for components that are important to the design but which exceed the prescriptive requirements. In total, these tradeoffs must

R405.3 PERFORMANCE-BASED COMPLIANCE Compliance using the performance approach requires a simulation of annual energy usage. In the simulation, a model of the proposed building must have a lower energy cost as compared to an energy cost index (ECI) of a standard reference design. Alternatively, the code permits an energy use simulation using the source energy relative to the conditioned floor area, expressed in Btu/ft2. Off-site renewable energy is considered the same as any other energy source but on-site renewable energy can be excluded from the simulation.

be as efficient as the standard reference design.

R405.2 MANDATORY REQUIREMENTS In addition to providing a compliant energy model, the building must also comply with all mandatory sections in R401.2.

H T A P E C N A M R O F R E P : L A I T N E D I S E R


R405.4 DOCUMENTATION R405.4.3 ADDITIONAL DOCUMENTATION The design professional must submit a compliance report that documents that the proposed design has annual energy costs less than or equal to the standard reference design.

R405.4.1 COMPLIANCE SOFTWARE TOOLS The documentation should include the software used for the analysis, verifying its methods and accuracy.

R405.4.2 COMPLIANCE REPORT

The compliance report on theproposed design must be submitted with the application for the building permit. When the building has been completed, a separate compliance report based on the as-built condition of the building must be submitted to the code official before it can receive a certificate of occupancy.

In addition to the documentation outlined above, the code official also has the right to ask for any of the following: • Documentation of the standard reference design building component characteristics • A certification signed by the builder providing the building component characteristics of the proposed design, according to Table R405.5.2(1) • Documentation of the actual values used in the calculations of the proposed design

R405.5 CALCULATION PROCEDURE To calculate the standard reference design, use the values in Table R405.5.2(1)

These reports must include the following information:

R405.4.2.1

R405.4.2.2

Compliance Report for Permit Application

Compliance Report for Certificate of Occupancy

Once the standard reference design has been configured and analyzed, a model of the proposed design using the same methods must show that it uses less or equal energy than the standard reference design.

Building address and identification information A statement that the proposed design complies with the baseline energycost requirement

A statement that the as-built building complies with the baseline energycost requirement

The inspection checklist A certificate indicating found in Table R405.5.2(1) the building passes the performance matrix for code compliance, and listing the energy-saving features of the building A site-specific energy analysis report The name of the person completing the compliance report The name and version of the software used Fig X.XXX


R405.6 CALCULATION SOFTWARE TOOLS The code lays out specific requirements for the software used to calculate the annual energy consumption of all building elements. Although any software meeting the requirements in R405.6.1 is allowed, REM/Rate is widely used. The code official may also authorize tools for a specified application or limited scope.

R406 ENERGY RATING INDEX COMPLIANCE ALTERNATIVE The Energy Rating Index (ERI) is a new compliance path that provides designers with more flexibility than the prescriptive path. The ERI is similar to the RESNET HERS index: • Each home is rated and given a score on the scale that coincides with its potential energy use. • A score of 0 is the rough equivalent ofa net-zero home, meaning that the home produces an equivalent amount of energy to the amount it uses. • The baseline ERI reference design (score of 100) is a theoretical home that meets minimum 2006 IECC prescriptive requirements. • Each incremental integer value equals 1% additional total energy use of the rated design, relative to the reference design. ERI differs from the performance and prescriptive path in several ways. Firstly, ERI considers all of the energy used in the residence, not just the fuel used in heating, cooling and service hot water heating systems. It also takes into account major appliances and plug loads. ERI allows equipment and appliance efficiencies to be involved in tradeoffs. ERI still requires that mandatory provisions of the code be met. However, for building thermal envelope efficiency and SHGC requirements, the ERI method references the 2009 IECC tables, which are more lenient.

DOCUMENTATION AND COMPLIANCE ERI ratings must be third party verified. Currently, projects that choose this pathway must employ a HERS rater to inspect the residence for proper insulation, provide the blower door test and provide the rating. In Climate Zone 5, a rating of 55 or below meets compliance and in Climate Zones 4 and 6 a rating


160... 150 140 130

ERI compliance path minimum requirements by Climate Zone:

CZ 4

C Z5

CZ 6

54

55

54

120 110 100 90

100 = 2006 IECC code-compliant house (baseline)

80 70 60 50 40 30 20 10 0

30 29 28 27 26 25 24 23 22 21 20

Each step between 0 and 100 indicates a 1% energy use increase between a net-zero home and the baseline reference design.

0 = Net-zero energy house

The ERI pathway is very similar to the HERS rating index, with 0 being a net-zero design and 100 being the standard reference design

of 54 or below complies. Having a HERS Rater as part of the design team can be a great resource to help simplify the compliance process and deliver a higher-performing building. The code stipulates documentation, software, and compliance report requirements similar to those in the performance path, although this process is simplified by having a third-party rater involved. The applicant will still be required to file the results with the code official.

X E D IN S R E H : L A I T N E D I S E R

CHAPTER 5 EXISTING BUILDINGS Implementing stricter energy codes on new construction will go a long way to reduce energy consumption in buildings across the state. However, 85% of the buildings that will exist in 2030 already exist and represent a challenge for reducing energy use. The energy code recognizes the difficulties involved with improving the performance of these buildings. The term “existing buildings” refers to buildings constructed before the code’s provisions took effect. The IECC does not require a legally-constructed existing building or system to comply with the current energy code provisions, but does require any new additions and alterations to comply. Note also that the “50% Rule” is no longer in effect—the exemption for renovations, additions, and alterations from being subject to the current state energy code unless the project affected more than half of the building’s systems. Now, any work that is not a repair or maintenance and affects energy use must meet the same requirements as for new construction.

R501 GENERAL

R503 ALTERATIONS

There are some exemptions for existing buildings. Historic buildings may be exempt, however, the design professional or preservation officer must submit a report to show that compliance would interfere with the historic nature of the building. The envelope requirements in some very low energy buildings may be exempt, for example a storage shed. Some renovation projects may be exempt if they do not affect the energy use of the building. Please note, even if the project is exempt, documentation needs to be provided to the

Although any alteration must comply, unaltered adjacent building components do not need to be brought up to code. There are some exceptions listed in the code: • Storm windows installed over existing fenestrations • Window film installed on existing single-pane assemblies

code official proving that the project is exempt.

• Existing insulation in cavities exposed during construction

R502ADDITIONS

• Construction where the existing roof, wall, or floor cavity is not exposed

Additions can comply in two ways: The addition can comply separately, or the addition and existing building can comply as a single building. All mechanical systems and water heating systems must comply with same provisions as new construction.

• Roof recover • When less than 50% of the luminaries in a space are being replaced, assuming the installed lighting power doesn’t increase Note that ASHRAE 90.1 2013 is more stringent; if replacing over 10% of the luminaires, it needs to be code compliant.

REPAIRS AND MAINTENANCE

ALTERATIONS

don’t need to be brought up to code

Must comply with Code

Unaltered adjacent elements don’t need to comply


S G N I D L I U B G IN T IS X E : L IA T N E ID S E R

DOCUMENTATION & INSPECTIONS While it is important to understand the specific code provisions, it is equally important to understand how to prove that the project complies to the enforcement entity. Lack of proper documentation is often the reason that plans are denied. Projects that are noncompliant will be delayed or stopped altogether until the designs are compliant and inspections are passed. This chapter includes easyto-follow guides for documentation and progress inspections. For residential projects, the most common objections include improperly specified or installed insulation. Specifically, the slab is not properly insulated and the interior foundation walls and ceilings have no insulation at all. Other reasons include the lack of air sealing and inappropriately sized cooling systems. Interestingly, insulation is not the main documentation problem for commercial projects, rather the lack of details and documentation for fenestration, air sealing, duct sealing, HVAC, Service Hot Water, and LPD calculations and controls. Pay particular attention to documenting these building components when ready to submit the construction documents to the code official.

COMMON COMPLIANCE ERRORS

Common technical mistakes include: • The project has filed for residential when they should have filed for commercial, or vice versa.

80%

80% of objections are due to documentation errors.

• Technical plans do not show a high-enough level of detail. »

»

Common administrative mistakes include: • Documents incorrectly filled out • Incomplete supporting documentation »

»

Just a COM/REScheck / energy model isn’t enough for compliance. Backup documentation that the analysis shown relates to that building is lacking.

Show proper detailing of continuous versus batt insulation and air sealing details. Show required HVAC performance data including efficiencies, controls, and R-values of duct insulation.

• Energy-related window information is not properly listed on the window schedules and tagged to the exterior elevations • U-Factors cannot besimply be listed. The calculations behind how the number was derived must be shown. »

Show both horizontal and vertical sections

• On NYC’s TR-8 form, usually all boxes need to be filled out. Often a box is left unchecked.


N O I T A T N E M U C O D

C/R103 CONSTRUCTION DOCUMENTS C/R103.1 GENERAL

C103.3 EXAMINATION OF

The construction documents must be submitted to the code official with the project filing.

DOCUMENTS

C/R103.2 INFORMATION ON CONSTRUCTION DOCUMENTS

When the code official decides that the construction documents meet the requirements of the energy code, they will stamp them as “Reviewed for Code Compliance,” meaning that they areapproved. Once the documents are approved, a copy will be sent back to the applicant and one will be kept by the code official.

The construction documents must represent the entire project, including the building thermal envelope, HVAC, service water heating, and lighting and electrical power systems.

When the documents are accepted, no further changes can be made without authorization from the code official. Any changes made without authorization must resubmit for approval.

Key each wall type, window type, HVAC unit, lighting fixture, etc., to their locations in the drawings and show where all supporting documentation for every item can be found, and indicate how the design complies.

Phased approval of individual components may also be pursued at the discretion of the code official. Most Used Method Commercial 693 700

The code stipulates includingat least the following in

600

the construction documents: Both Commercial and Residential:

500 400

• Insulation materials and their R-values • Fenestration U-factorand solar heat gain coefficient (SHGC) calculations

246

300 200

41

100

• Area-weighted U-Factor and solar heat gain coefficients (SHGC) calculations

h c

CO

k c e

M

ad Tr

ff eo P

t rip sc re

e iv

O

• Mechanical system design criteria • Mechanical and service water heating system and equipment types, sizes and efficiencies 800

• Duct sealing, duct pipe insulation, and location

600

• Air sealing details

50

e ar tw of s r

t ee sh ro k W

79

e th

gy er En

al An

is ys

Most Used Method Residential

• Equipment and system controls

Commercial Only:

41

0

703

700

500 400

289

300 200

• Economizer description • Fan motor horespower (hp) and controls • Lighting fixture schedule with wattage and control narrative • Location of daylight zones on floor plans

51

100

45

59

e twar os f r

t shee ro k W

70

0

h c

S RE

ck e

ad Tr

eoff P

e riptiv se c r O

e th

gy er En

is alys An

These charts show how often each method of compliance is used.



C/R104 INSPECTIONS C/R104.1 GENERAL

APPROVAL PROCESS

The inspection process will vary by locality, but certain inspections are laid out in the energy code itself. It is the responsibility of the applicant to inform the code official when each component is ready to be inspected.

The applicant must inform the code official when each component is ready for inspection and provide ready access to the site for the inspector.

Ensure that all components are inspected while they are still exposed. The code explicitly states that the applicant is responsible for the cost of removing materials if necessary to complete the inspection.

and the work can be corrected and resubmitted. If the issue is not corrected (or during any other point in the approval process, if the code official deems that the work doesn’t comply with the energy code), they may issue a stop work order. If the issue is not addressed, the building will not receive a certificate of occupancy.

The code inspector will also make sure that the work that is being observed is the same as what is indicated in the approved construction documents (see C/R103)

C/R104.2 REQUIRED INSPECTIONS

If the inspection is failed, a notice of deficiency is issued

If the applicant feels that their filing was unfairly rejected, there is a board of appeals that is able to review the process. The board does not have the authority to waive the code however—only to determine if a previous decision was unfair.

INSPECTION COMMERCIAL

RESIDENTIAL

Footing and foundation inspection

• R-value, location, thickness, depth of burial, and protection of insulation

Framing and rough-in

• Made before application of interior finish

inspection Plumbing rough-in inspection

and installation; and air leakage • Types of insulation and corresponding R-values and protection; required controls; and required heat traps

Mechanical rough-in inspection

• Installed HVAC equipment type and size; required controls; system insulation and corresponding R-value; system and damper air leakage; and required energy recovery and economizers

• Insulation and corresponding R-values, location and installation; fenestration properties • Types of insulation and corresponding R-values and protection; and required controls • Installed HVAC equipment type and size; required controls; system insulation and corresponding R-Value; system air leakage control; programmable thermostats; dampers; whole-house ventilation; and minimum fan efficiency • Systems serving multiple dwelling units will be inspected according to the commercial section

Electrical rough-in inspection

• Installed lighting systems, components and controls, and installation of an electric meter for each dwelling unit (submetering)

• Not required

Final inspection

• Verification that required building

• Verification of the installation of all

controls were installed and work correctly; commissioning was completed; and any findings of non-compliance have been corrected • The building cannot be considered for a final inspection until the applicant has received the Preliminary Commissioning Report (from C408.2.4) 68 DRAFT FOR REVIEW: NOT PROOFREAD

required building systems, equipment and controls, and their proper operation and required number of high-efficacy lamps and fixtures

QUICK GUIDE TO DOCUMENTATION DETAILS: COMMERCIAL C103.2 INFORMATION ON CONSTRUCTION DOCUMENTS

Drawings must: q Be drawn to scale q Indicate the location, nature, andextent of the work proposed q Detail pertinent data and features of the building, systems and equipment Drawings must show: Envelope q Insulation materials and their R-values q Fenestration U-factorsand solar heat gain coefficients (SHGCs) q Area-weighted U-factor and solar heat gain coefficient (SHGC) calculations q Air sealing details q Building thermal envelope depiction Mechanical q Mechanical system design criteria q Mechanical and service water heating system and equipment types, sizes and efficiencies. q Economizer description q Equipment and system controls (including narrative describing function, operationand setpoints) q Fan motor horsepower (hp) and controls q Duct sealing, duct and pipe insulation and location Lighting and Electrical Power q Lighting fixture schedule with wattage and control narrative q Location of daylight zones on floor plans Commissioning q Construction document indicates provisions forcommissioning and completion requirements q Create a commissioning plan q Submit commissioning documents to the owner q Submit commissioning statement toDOB that says the project complies withor is exempt from commissioning requirements

QUICK GUIDE TO DOCUMENTATION DETAILS: RESIDENTIAL R103.2 INFORMATION ON CONSTRUCTION DOCUMENTS

Drawings must: q Be drawn to scale q Indicate the location, nature, andextent of the work proposed q Detail pertinent data and features of the building, systems and equipment Drawings must show: Envelope q Insulation materials and their R-values. q Fenestration U-factorsand solar heat gain coefficients (SHGC). q q q

Area-weighted U-factor and solar heat gain coefficients (SHGC) calculations. Air sealing details Building thermal envelope depiction

Systems q Mechanical system design criteria. q Mechanical and service water-heating system and equipment types, sizes and efficiencies. q Equipment and system controls. q Duct sealing, duct and pipe insulation and location.



PROGRESS INSPECTIONS Progress inspections verify that the construction matches the construction documents. Progress inspectors will identify if the envelope, systems, service water heating, electrical, and other building components are installed according to code requirements. Progress inspectors are registered design professionals with relevant experience. They are hired by the Owner from an approved Progress Inspection Agency. The registered design professional of record can act as the inspector but the contractor cannot (NYC rule). Otherwise, the progress inspector must have a minimum of 5 years experience with energy code-related building systems (for commercial buildings, at least 3 of those years must be related to the systems being inspected). Where an inspection or test fails, the construction shall be corrected and must be made available for re-inspection and/or retesting by the progress inspector until it complies.

ENERGY CODE QUICK GUIDE: PREPARING FOR PROGRESS INSPECTIONS Provide a clear inspection list on construction drawings to show contractors what inspectors are looking for and when to schedule. Schedule progress inspections before roofs, ceilings, exterior walls, interior walls, floors, foundations, basements and any other construction is enclosed. WHAT INSPECTORS ARE LOOKING FOR: ENVELOPE q Visually inspect insulation and air sealing details q Confirm insulation R-value q Confirm fenestration labelsfor U-factor, SHGC, VT q Confirm that dimensions of windows, doors and skylights match drawings q Check that penetrations are properly sealed q Visually inspect vestibules, loading docks and projections q Report results of blower door test MECHANICAL & PLUMBING q Confirm tight-fitting fireplace doors q Test a min. of 20% of shutoff dampers for proper operation q Visually inspect thatHVAC and hot water equipment matches dra wings. Check ratedefficiencies q Confirm that installed controls match drawings for functionality and set points q Visually inspect duct and pipe insulation q Test a minimum of 20% of ducts for leakage ELECTRICAL POWER AND LIGHTING q Visually inspect submeters and high-efficacy lamps Commercial: q Visually inspect light fixtures to confirm lighting power allowance q Visually inspect exterior lighting fixtures q Visually inspect lighting controls and test for functionality andproper operation q Check exit signs and motors for compliance OTHER: q Are maintenance manuals present? Do they match equipment? q Is Permanent Certificate installed?



NYSERDA New York State Energy Research & Development Authority 17 Columbia Circle Albany, New York 12203 (518) 862-1090 www.nyserda.org


Energy Code Workbook v0.95.pdf

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