31-004 Code Vt. R. 31-000-004-X
Preface
delete and replace Preface as follows:
Introduction
The 2024 Vermont Residential Building Energy Standards (RBES) is based on the 2020 Vermont Residential Building Energy Standards, which are based on the 2018 and 2015 International Energy Conservation Code ®(IECC®). The 2024 RBES also includes 2021 and 2018 IECC energy efficiency requirements as well as select language updates and additional, more stringent Vermont energy efficiency requirements.
This comprehensive energy conservation code establishes minimum regulations for energy efficient buildings using prescriptive and performance-related provisions. It is founded on broad-based principles that make possible the use of new materials and new energy efficient designs.
The International Energy Conservation Code provisions provide many benefits, among which is the model code development process that offers an international forum for energy professionals to discuss performance and prescriptive code requirements. This model code also encourages international consistency in the application of provisions.
Development
This 2024 RBES is founded on principles intended to establish provisions consistent with the scope of an energy conservation code that adequately conserves energy; provisions that do not unnecessarily increase construction costs; provisions that do not restrict the use of new materials, products or methods of construction; and provisions that do not give preferential treatment to particular types or classes of materials, products or methods of construction.
Background
The Vermont Residential Building Energy Standards (RBES) was adopted by statute (30 V.S.A. §51) in 1997. Act 89 of 2013 established a Stretch Code defined as a building energy code for residential buildings that achieves greater energy savings than the RBES. The stretch code shall be available for adoption by municipalities under 24 V.S.A. §117 and shall apply in proceedings under 10 V.S.A. §151 (Act 250). Update Process The Residential Building Energy Standards statute requires that revisions to the RBES are made promptly after the issuance of updated standards under the International Energy Conservation Code (IECC). The Department of Public Service (PSD) is required to convene stakeholders that include mortgage lenders, builders, building designers, utility representatives, and other persons with experience and expertise prior to the adoption of a revised RBES to provide recommendations.
The 2024 RBES is based on the language in the 2015 edition of the IECC and includes efficiency improvements included in the 2018 and 2021 IECC to ensure continued progression in efficiency in the Vermont RBES. The 2024 RBES builds on the "Package Plus Points" approach to code compliance, initiated in 2020. (Previous code compliance was achieved through a "prescriptive package" approach). The addition of "points" provides builders and designers greater flexibility in complying with the RBES. The 2024 RBES also simplified the Packages and makes them applicable to both the Base Code and the Stretch Code, with the only difference being the number of Points needing to be achieved. The 2024 RBES also attempts to better address multifamily construction by aligning the standards between RBES and the Commercial Building Energy Standards (CBES) so that regardless of whether the multifamily building falls under RBES (up to three stories in height) or CBES (buildings four stories or higher), the energy standards should be consistent. The Code Collaborative Process undertaken in 2021 allowed for more in-depth discussions with stakeholders on topics and many of the suggestions are reflected in the 2024 RBES. The Vermont PSD also held a series of stakeholder meetings in 2022 to gather feedback on proposed changes to the RBES. The revisions presented in this document were modified based on input received from these meetings.
EFFECTIVE USE OF THE 2024 VERMONT RESIDENTIAL BUILDING ENERGY STANDARDS
The 2024 Vermont Residential Building Energy Standards (RBES) is a code that regulates minimum energy conservation requirements for new buildings as well as additions, alterations, renovations, and repairs to existing buildings. The 2024 RBES addresses energy conservation requirements for all aspects of energy uses in residential construction, including heating and ventilating, lighting, water heating, and power usage for appliances and building systems.
The 2024 RBES is a design document. For example, before constructing a building, the designer must determine the minimum insulation R-values and fenestration U-factors for the building exterior envelope. The RBES sets forth minimum requirements for exterior envelope insulation, window and door U-factors and SHGC ratings, duct insulation, lighting and power efficiency, mechanical ventilation, and water distribution insulation.
Arrangement and Format of the 2020 RBES
The 2024 RBES, like other codes published by ICC, is arranged and organized to follow sequential steps that generally occur during a plan review or inspection. The 2024 RBES is divided into six different parts:
Chapters | Subjects |
1-2 | Scope, Administration and Definitions |
3 | General Requirements |
4 | Residential Energy Efficiency |
5 | Existing Buildings |
6 | Referenced Standards |
The following is a chapter-by-chapter synopsis of the scope and intent of the provisions of the 2024 Vermont Residential Building Energy Standards:
The terms defined in Chapter 2 are deemed to be of prime importance in establishing the meaning and intent of the code text. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and the user may not be aware that a term is defined.
Where understanding of a term's definition is especially key to or necessary for understanding of a particular code provision, the term is shown in italics wherever it appears in the code. This is true only for those terms that have a meaning that is unique to the code. In other words, the generally understood meaning of a term or phrase might not be sufficient or consistent with the meaning prescribed by the code; therefore, it is essential that the code-defined meaning be known.
Guidance regarding tense, gender and plurality of defined terms as well as guidance regarding terms not defined in this code is provided.
Chapter 6 is organized in a manner that makes it easy to locate specific standards. It lists all of the referenced standards, alphabetically, by acronym of the promulgating agency of the standard. Each agency's standards are then listed in either alphabetical or numeric order based upon the standard identification. The list also contains the title of the standard; the edition (date) of the standard referenced; any addenda included as part of the ICC adoption; and the section or sections of this code that reference the standard.
Italicized Terms
Selected terms set forth in Chapter 2, Definitions, are italicized where they appear in code text. Such terms are not italicized where the definition set forth in Chapter 2 does not impart the intended meaning in the use of the term. The terms selected have definitions that the user should read carefully to facilitate better understanding of the code.
Marginal Markings
Solid vertical lines in the margins within the body of the code indicate a technical change from the requirements of the IECC 2015 and 2018 edition. Vermont specific additions and changes are designated through dotted lines in the margin. Deletion indicators in the form of an arrow (RIGHT ARROW') are provided in the margin where an entire section, paragraph, exception or table has been deleted or an item in a list of items or a table has been deleted.
Abbreviations and Notations
The following is a list of common abbreviations and units of measurement used in this code. Some of the abbreviations are for terms defined in Chapter 2. Others are terms used in various tables and text of the code.
AFUE Annual fuel utilization efficiency
bhp Brake horsepower (fans)
Btu British thermal unit
Btu/h-ft [2]Btu per hour per square foot
C-factor See Chapter 2--Definitions
CDD Cooling degree days
cfm Cubic feet per minute
cfm/ft [2]Cubic feet per minute per square foot
ci Continuous insulation
COP Coefficient of performance
DCV Demand control ventilation
°C Degrees Celsius
°F Degrees Fahrenheit
DWHR Drain water heat recovery
DX Direct expansion
[E] c Combustion efficiency
[E] v Ventilation efficiency
[E] t Thermal efficiency
EER Energy efficiency ratio
EF Energy factor
ERI Energy Rating index
F -factor See Chapter 2--Definitions
FDD Fault detection and diagnostics
FEG Fan efficiency grade
FL Full load
ft [2]Square foot
gpm Gallons per minute
HDD Heating degree days
HERS Home Energy Rating System
hp Horsepower
HSPF Heating seasonal performance factor
HVAC Heating, ventilating and air conditioning
IEER Integrated energy efficiency ratio
IPLV Integrated Part Load Value
Kg/m [2]Kilograms per square meter
kW Kilowatt
LPD Light power density (lighting power allowance)
L/s Liters per second
Ls Liner system
m [2]square meters
MERV Minimum efficiency reporting value
NAECA National Appliance Energy Conservation Act
NPLV Nonstandard Part Load Value
Pa Pascal
PF Projection factor
pcf Pounds per cubic foot
PSD Department of Public Service (Vermont)
psf Pounds per square foot
PTAC Packaged terminal air conditioner
PTHP Packaged terminal heat pump
R -value See Chapter 2--Definitions
SCOP Sensible coefficient of performance
SEER Seasonal energy efficiency ratio
SHGC Solar Heat Gain Coefficient
SPVAC Single packaged vertical air conditioner
SPVHP Single packaged vertical heat pump
SRI Solar reflectance index
SWHF Service water heat recovery factor
U -factor See Chapter 2--Definitions
VAV Variable air volume
VRF Variable refrigerant flow
VT Visible transmittance
W Watts
w.c. Water column
w.g. Water gauge
delete and replace R101.1 Title.
This code shall be known as the 2024 Vermont Residential Building Energy Standards (RBES) and shall be cited as such. It is referred to herein as "this code."
delete and replace R101.2 Scope.
This code applies to residential buildings and the building sites and associated systems and equipment, including one family dwellings, two family dwellings, and multi-family housing three stories or less in height.
For the purpose of determining the building type that must comply with the RBES under Vermont statute, a multifamily building is a residential building or mixed-use building with three or more dwelling units three stories or less in height. Multifamily buildings of four stories or more in height must comply with the CBES (from Vermont 30 V.S.A. §51.)
While many sections of this code (e.g., inspections, review of construction documents, compliance, etc.) do not pertain to most of Vermont that lacks a code official or authority having jurisdiction, these sections are included to provide guidance for those jurisdictions that do have a code official or authority having jurisdiction.
delete and replace R101.7 Base and Stretch Code.
The " Base Code" is the RBES Energy Code that is applicable throughout Vermont, except for projects subject to 10 V.S.A. Chapter 151 (Act 250), and in any municipalities that have adopted the more stringent "Stretch Code."
All Base Code requirements shall be met in addition to the requirements in the Stretch Code section R407 in order to be in compliance with the Stretch Code.
delete and replace R101.8 Compliance options.
There are three thermal efficiency compliance options:
A HERS energy rating that demonstrates compliance with Section 406.4 for the Base or Stretch Code based on REM v16.3.3 or later or Ekotrope version 4.0 or later that is accredited by RESNET at https://www.resnet.us/providers/accredited-providers/hers-software-tools/.
delete and replace R103.1 General.
Where required, construction documents, technical reports and other supporting data shall be submitted in one or more sets, or in a digital format where allowed by the code official or authority having jurisdiction, where one exists, with each application for a permit. The construction documents and technical reports shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. Where special conditions exist, the code official or authority having jurisdiction, where one exists, is authorized to require necessary construction documents to be prepared by a registered design professional.
Exception: The code official or authority having jurisdiction, where one exists, is authorized to waive the requirements for construction documents or other supporting data if the code official or authority having jurisdiction, where one exists, determines they are not necessary to confirm compliance with this code.
delete and replace R103.2 Information on construction documents.
Where required, construction documents shall be drawn to scale upon suitable material. Electronic media documents are permitted to be submitted where approved by the code official or other authority having jurisdiction, where one exists. Construction documents shall be of sufficient clarity to indicate the location, nature and extent of the work proposed, and show in sufficient detail pertinent data and features of the building, systems and equipment as herein governed. Details shall include, but are not limited to, the following as applicable:
Delete and replace section R104 and subsections as follows:
Where required, construction or work for which a permit is required shall be subject to inspection by the code official or other authority having jurisdiction, where one exists, or his or her designated agent, and such construction or work shall remain visible and able to be accessed for inspection purposes until approved. It shall be the duty of the permit applicant to cause the work to remain visible and able to be accessed for inspection purposes. Neither the code official nor the jurisdiction shall be liable for expense entailed in the removal or replacement of any material, product, system or building component required to allow inspection to validate compliance with this code.
add ACCESS (TO). That which enables a device, appliance, or equipment to be reached by ready access or by a means that first requires the removal or movement of a panel or similar obstruction.
delete and replace AIR BARRIER. An air barrier is a durable assembly that blocks air flow through the building thermal envelope and its assemblies. Air barriers must be continuous, sealed at all joints, penetrations, and interruptions using durable sealants intended for such use and compatible with all adjacent materials, and able to resist pressures without displacement or damage.
add BUILDING SHELL AREA. The sum of the area of ceiling, floors, and walls, slab (all "six sides") separating a dwelling unit's conditioned space from the exterior or from adjacent conditioned or unconditioned spaces. Wall height shall be measured from the finished floor of the dwelling unit to the underside of the floor above.
delete and replace BUILDING SITE. A contiguous area of land that is under the ownership or control of one entity.
add CARBON DIOXIDE EQUIVALENT (CO2E). A measure used to compare the impact of various greenhouse gases based on their global warming potential (GWP). CO2e approximates the warming effect of a unit mass of a given greenhouse gas relative to that of carbon dioxide (CO2).
add CAVITY INSULATION. Insulating material located between framing members.
delete and replace CLIMATE ZONE. A geographical region based on climatic criteria as specified in this code. Vermont is Climate Zone 6.
delete DEADBAND. The temperature range in which no heating or cooling is used.
add DEMAND RESPONSE SIGNAL. A signal that indicates a price or a request to modify electricity consumption for a limited time period.
add DEMAND RESPONSIVE CONTROL. A control capable of receiving and automatically responding to a demand response signal.
add DIMMER. A control device that is capable of continuously varying the light output and energy use of light sources.
add ELECTRIC VEHICLE CHARGING - LEVEL 2 CAPABLE. Level 2 "capable" includes space in the utility room for panel(s) of at least one minimum 40-ampere branch circuit to be provided to garages and/or the exterior of the building to accommodate a future dedicated Society of Automotive Engineers (SAE) standard J1772-approved Level 2 EVSE with a J1772 connector or NEMA 14-50, or equivalent, within 5 feet of the centerline for each EV charging parking space. A conduit or other unobstructed path to easily run a future wire to the parking spot shall also be provided.
add ELECTRIC VEHICLE CAPABLE PARKING SPACE. A parking space with all the requisite infrastructure in place within five feet to allow electrical wiring and connection to power for EVSE.
delete and replace ELECTRIC VEHICLE SUPPLY EQUIPMENT (EVSE). Level 2 electric vehicle charging parking that requires one 208/240V 40 amp grounded connection for electric vehicle charging through dedicated EVSE with J1772 connector or AC receptacle, NEMA 14-50, or equivalent, within 5 feet (1524 mm) of the centerline for each EV charging parking space.
add GLOBAL WARMING POTENTIAL (GWP). GWP is an index for estimating the relative global warming contribution of atmospheric emissions of 1 kg of a particular greenhouse gas compared to emissions of 1 kg of CO2. The following GWP values are used based on a 100-year time horizon: 1 for CO2, < 10 for pentane (e.g., C5H12), and 1430 for R-134a (CH2FCF3).
add GLOBAL WARMING POTENTIAL (GWP) INTENSITY. For the purposes of this document, GWP intensity refers to the GWP impact from materials (kg CO2e) divided by the project's total conditioned floor area in square feet (ft2).
delete HIGH-EFFICACY LAMPS/ LIGHTING.
add HIGH-EFFICACY LIGHT SOURCES. Non-linear medium screw- and pin-base lamps with a minimum efficacy of not less than 65 lumens per watt; or light fixtures of not less than 65 lumens per watt. In determining the number or percent of lamps, each replaceable lamp (or light string) connected to a permanently installed lighting fixture shall count as one lamp.
delete LEVEL 1 ELECTRIC VEHICLE CHARGING.
delete LEVEL 2 ELECTRIC VEHICLE CHARGING.
delete and replace LIGHTING. See "High-efficacy light sources."
delete and replace MULTIFAMILY DWELLING/BUILDING. A building containing three or more dwelling units where the occupants are primarily permanent in nature and which are adjacent vertically or horizontally. If built side-by-side, at least one of the following is true:
add NET ZERO ENERGY READY. A highly efficient and cost-effective building designed and constructed so that renewable energy could offset all or most of its annual energy consumption.
add OCCUPANT SENSOR CONTROL. An automatic control device that detects the presence or absence of people within an area and causes lighting, equipment or appliances to be regulated accordingly.
add ON-SITE RENEWABLE ENERGY GENERATION. Energy from renewable energy resources that is generated at the building site.
add READY ACCESS (TO). That which enables a device, appliance, or equipment to be directly reached without requiring the removal or movement of any panel or similar obstruction.
add RENEWABLE ENERGY CERTIFICATE (REC). An instrument that represents the environmental attributes of one megawatt hour of renewable energy; also known as an energy attribute certificate (EAC).
delete RENEWABLE ENERGY SOURCES.
add RENEWABLE ENERGY RESOURCES. Energy produced using a technology that relies on a resource that is being consumed at a harvest rate at or below its natural regeneration rate including, but not limited to, solar hot water, solar hot air, solar photovoltaics, wind, and hydro.
delete and replace SOLAR ENERGY SOURCE. Source of thermal, chemical, or electrical energy derived directly from conversion of incident solar radiation.
delete and replace STRETCH CODE. A building energy code that achieves greater energy savings than the B RBES Base Code. The Stretch Code is required for Act 250 projects and may be adopted by municipalities.
add THERMAL DISTRIBUTION EFFICIENCY (TDE). The resistance to changes in air heat as air is conveyed through a distance of air duct. TDE is a heat loss calculation evaluating the difference in the heat of the air between the air duct inlet and outlet caused by differences in temperatures between the air in the duct and the duct material. TDE is expressed as a percent difference between the inlet and outlet heat in the duct.
add TINY HOUSE. A detached dwelling unit of less than 400 square feet of floor area excluding lofts.
add TYPE III PRODUCT-SPECIFIC ENVIRONMENTAL PRODUCT DECLARATION (EPD). An EPD is a document that describes the results of a life cycle assessment (LCA) for a material or product. While there are industry-specific EPDs, which average results across multiple product manufacturers, product-specific EPDs are the most thorough type of EPD. Type III, product-specific EPDs cover a single product from a manufacturer and are reviewed by a third-party entity. They conform to ISO 14025 and either EN 15804 or ISO 21930. Like all product specific EPDs, the scope must cover the product's life-cycle from cradle to gate.
add R302.2 Climatic data.
The following design parameters in Table 302.2 shall be used for calculations required under this code.
Adjustments may be made only in the following cases:
delete and replace R303.1.2 Insulation mark installation.
Insulating materials shall be installed such that the manufacturer's R-value mark is readily observable upon inspection. For insulation materials that are installed without an observable manufacturer's R-value mark, such as blown or draped products, an insulation certificate complying with Section R303.1.1 shall be left immediately after installation by the installer, in a conspicuous location within the building, to certify the installed R-value of the insulation material.
add R303.1.5 Air-impermeable insulation.
Insulation having an air permeability not greater than 0.004 cubic feet per minute per square foot [0.002 L/(s x m2)] under pressure differential of 0.3 inch water gauge (75 Pa) when tested in accordance with ASTME2178 shall be determined air-impermeable insulation.
delete and replace R303.1.1.1 Blown or sprayed roof and ceiling insulation.
The thickness of blown-in or sprayed roof/ceiling insulation (fiberglass or cellulose shall be written in inches (mm) on markers that are installed at least one for every 300 square feet (28 m [2)] throughout the attic space. The markers shall be affixed to the trusses or joists and marked with the minimum initial installed thickness with numbers not less than 1 inch (25 mm) in height. Each marker shall face the attic access opening. Spray polyurethane foam minimum thickness and installed R -value shall be listed on certification provided by the insulation installer.
delete and replace R304.1 Scope.
This section shall govern ventilation of the dwelling unit(s) within Type R-1 residential buildings, Type R-2 residential buildings and multiple single-family attached dwellings (townhouses and multifamily buildings) not more than three stories in height.
delete and replace R304.1.1 Compliance.
Compliance with Section 304 shall be achieved by installing a whole house balanced ventilation system with minimum 75 SRE and 1.2 cfm/Watt, determined in accordance with HVI Publication 920 and listed in HVI Publication 911, while also meeting compliance with Sections 304.2 through 304.11 or demonstrating compliance with one of the following alternatives:
Residential Buildings)
Exception
delete and replace 304.2 Local ventilation.
Ventilation fans in bathrooms containing a bathtub, shower, spa or similar bathing fixture and not included in the whole house ventilation system shall be sized to meet the net capacity rates as required in Table 304.2. Whole house ventilation fans serving both localized and whole house ventilation functions shall be sized to meet the net capacity rates as required by Section 304.6 and must meet all other requirements listed in Section 304.3, as applicable.
TABLE 304.2
MINIMUM REQUIRED LOCAL EXHAUST
OCCUPANCY CLASSIFICATION | MECHANICAL EXHAUST CAPACITY (CFM) |
Bathrooms | 50 cfm intermittent or 20 cfm continuous |
delete R304.3 Whole house balanced ventilation.
delete and replace R304.5 Fan motor requirements.
Fans installed for the purpose of providing whole house ventilation must meet the minimum requirements as specified in this section.
delete R304.5.2 Fan power consumption.
delete R304.5.34 Performance verification.
delete and replace R304.6 Net capacity requirements.
Whole house ventilation system fans shall be installed according to the manufacturer's installation instructions and shall have the manufacturer's fan flow ratings as listed in accordance with HVI 911. Unless the whole house system is tested according to procedures in Section R304.6.1, the minimum continuous flow rate that the ventilation system must be capable of supplying during its operation shall be based on the rate per bedroom as specified in Table R304.6.
TABLE R304.6
PRESCRIPTIVE FAN CAPACITY REQUIREMENTS FOR CENTRALLY DUCTED SYSTEMS
NUMBER OF BEDROOMS | MINIMUM NOMINAL RATED TOTAL FAN a CAPACITY (at 0.1 inches w.g.) |
1 | 50 cfm |
2 | 75 cfm |
3 | 100 cfm |
4 | 125 cfm |
5 | 150 cfm |
2 Homes > 3,000 ft | 2 cfm = 0.05 · ft |
For SI: 1 cubic foot per minute = 0.0004719 m /s, 1 cubic foot per minute per square foot = 0.00508 m /(s m).
delete and replace R304.6.1 Testing option.
Testing may be done for Points to verify that the whole house ventilation system satisfies the ventilation requirements of this section in accordance with Sections R304.6.1.1 and R304.6.1.2.
delete and replace R304.8 Controls.
Whole house ventilation systems (balanced ventilation) shall be capable of being set remotely for continuous operation or shall be provided with an automatic control for intermittent operation. All whole house ventilation controls shall be readily accessible.
Exception: Fans installed expressly for local ventilation purposes.
delete and replace R304.9.3 Ducts.
Smooth wall ducts (for example, metal or composite) must be used for all duct runs longer than 8 feet (2438 mm). Ducts shall be insulated when installed in an unheated location
add R304.9.9 Exhaust Dampers.
Dampers with positive closures shall be installed to keep outside air from entering the exhaust duct when the system is not operating.
Exception: Mechanical ventilation systems designed for continuous operation.
delete and replace R304.11 Makeup air required.
Exhaust hood systems and clothes dryers capable of exhausting in excess of 400 cubic feet per minute (0.19 m /s) shall be provided with makeup air at a rate approximately equal to the exhaust air rate. Such makeup air systems shall be equipped with a means of closure and shall be automatically controlled to start and operate simultaneously with the exhaust system.
delete and replace R401.1 Scope.
This chapter applies to residential buildings compliance with both the Base Code and Stretch Code. Stretch Code requires compliance with all Base Code requirements throughout RBES, plus achieving the additional points specified in Table R402.1.2.2, following all requirements of the following sections, and complying with Section R407 Vermont Stretch Code.
delete and replace R401.2 Compliance.
Projects for both Base Code and Stretch Code shall comply with one of the following:
delete and replace R401.3 Certificate of Compliance
An RBES certificate is required to be issued. The certificate should be issued upon completion and before occupancy of any project subject to the Residential Building Energy Standards. A certificate may be issued by a builder, a licensed professional engineer, a licensed architect or an accredited home energy rating organization. If certification is not issued by a licensed professional engineer, a licensed architect or an accredited home energy rating organization, it shall be issued by the builder. Any certification shall certify that residential construction meets the RBES. The Department of Public Service will develop and make available to the public a certificate that lists key features of the RBES. Any person certifying shall use this certificate or one substantially like it to certify compliance with the RBES. Certification shall be issued by completing and signing a certificate and affixing it to the electrical service panel, without covering or obstructing the visibility of the circuit directory label, service disconnect label or other required labels. The certificate shall certify that the residential building has been constructed in compliance with the requirements of the RBES. The person certifying under this subsection shall provide a copy of the certificate to the Department of Public Service and shall assure that a certificate is recorded and indexed in the town land records. A builder may contract with a licensed professional engineer, a licensed architect or an accredited home energy rating organization to issue certification and to indemnify the builder from any liability to the owner of the residential construction caused by noncompliance with the RBES.
delete and replace R402.1 General (Prescriptive).
The building thermal envelope shall meet the requirements of Sections R402.1.1 through R402.1.6.
Exceptions:
The following buildings, or portions thereof separated from the remainder of the building by building thermal envelope assemblies complying with this section shall be exempt from the building thermal envelope provisions of Section R402.
Any statement or certificate given to a prospective buyer shall itemize how the home does not comply with RBES and shall itemize which measures do not meet the RBES in effect at the time construction commenced.
delete and replace R402.1.1 Vapor retarder.
Wall assemblies and roof or ceiling assemblies which are part of the building thermal envelope shall comply with the vapor retarder requirements of Section R702.7 of the International Residential Code or Section 1405.3 of the International Building Code, as applicable, or with R402.2.15 in this document
delete and replace R402.1.2 Insulation and fenestration criteria.
The building thermal envelope shall comply with one of the following only:
Building science principles should be applied in all circumstances. Consult with a building science professional and refer to the Vermont Residential Energy Code Handbook for additional guidance and details.
delete and replace R402.1.2.1 Package Plus Points Approach.
Projects shall comply with Items 1 through 4: for both Base Code and Stretch Code:
delete and replace R402.1.2.1 Package Plus Points Approach.
Projects shall comply with Items 1 through 4: for both Base Code and Stretch Code:
add TABLE R402.1.2.1
TABLE R402.1.2.1
INSULATION AND FENESTRATION REQUIREMENTS BY COMPONENT FOR STANDARD PACKAGES FOR BASE CODE AND STRETCH CODE
Component | Package 1 | Package 2 |
"Standard Package" | "Log Homes" | |
Ceiling - flat atticg | U-0.020: R-49g | |
Ceiling - slope (no attic) | U-0.025: R-44 | |
Above Grade Wallb | U-0.044: R-21+5cie OR R-13+10ci OR R-20 6 1/2" ci (SIP) OR Other that meets U-factor | Construct log home walls to ICC 400--2022 Standard on the Design and Construction of Log Structures Table 305.3.1.2 or Vermont RBES Table R402.1.6 |
Frame Floor | U-0.029: R-38 | |
Basement/Crawlc | R-20ci OR R13+10ci | |
Slab, on graded | R-20,4' (edge) OR R-15,4'(edge) + R-7.5 (under entire slab) | |
Slab, on grade, Heatedd | R-20,4' (edge) + R-15 (under entire slab) | |
Windows | U-0.30 | |
Skylights | U-0.41 | |
Doors | U-0.37 | |
Air Leakage | 0.15 CFM50/Sq. Ft. of Building Shell (~2 ACH50)h | |
Ducts | Inside thermal boundary | |
For SI: 1 foot = 304.8 mm.
delete R402.1.2.2 Required Points by Building Size.
add R402.1.2.2 Required points by building or addition size.
Determine the number of points required by building or addition size from Table R402.1.2.2. Building size for this table is determined by the finished conditioned floor area per dwelling unit inside the building thermal envelope, including unfinished basements and storage/utility spaces.
The Multifamily less than 1,250 square feet (185.8 m) and 1,2500-2,500 square feet point requirement categories cannot be used for semi-detached (semi-attached, side-by-side), row houses, and townhouses, as defined as single-family dwellings in Section R202, General Definitions. Multifamily dwelling unit size is based on the average finished conditioned floor area dwelling size for the building, excluding common areas, hallways, stairwells, etc..
delete and replace TABLE R402.1.2.2
TABLE R402.1.2.2
REQUIRED POINTS BY BUILDING SIZE FOR BASE CODE AND STRETCH CODE
BUILDING/DWELLING SIZE | BASE CODE REQUIRED POINTS | STRETCH CODE REQUIRED POINTS |
Alterations | 0 | 0 |
Additions < 250 square feet | 0 | 0 |
Additions 250 to 500 square feet | 1 | 2 |
Addition 501 to 1,000 square feet | 2 | 3 |
Addition > 1,000 square feet | 3 | 4 |
Multifamily <650 square feet | 0 | 1 |
Multifamily 650 to 900 square feet | 1 | 2 |
Multifamily 900 to 1,250 square feet | 2 | 3 |
Multifamily >1,250 to 2,500 square feet | 4 | 5 |
< 2,500 square feet | 5 | 7 |
2,500 to 4,000 square feet | 7 | 12 |
> 4,000 square feet | 10 | 15 |
delete and replace TABLE R402.1.2.3
TABLE R402.1.2.3
POINTS BY COMPONENT FOR BASE CODE AND STRETCH CODE
Component | Description | Points | |
Envelope | Slab (on or below grade, heated or unheated) | R-20 around perimeter and below entire slab ORb | 2 |
R-25 around perimeter and below entire slab | 3 | ||
Walls | R-28 2x6 cavity insulation with continuous (R20+9ci or similar) (U-0.036 wall assembly) ORb | 1 | |
R-35 double stud or similar (cavity and continuous) (U-0.028 wall assembly) ORb | 2 | ||
R-40 double stud or similar (cavity and continuous) (U-0.025 wall assembly) ORb | 3 | ||
R-48 SIP 10 1/4" XPS or similar (cavity and continuous) (U-0.021 wall assembly) | 4 | ||
Ceiling | R-60 attic flats (U-0.018) and R-49 slopes, vaulted and cathedral (U-.020) | 1 | |
R-80 attic flats (U-0.013) and R-60 slopes, vaulted and cathedral (U-.018) | 2 | ||
Floors - Exposed | R-49 (U-0.021) | 1 | |
Windows-Triple Pane | Average U-factor $(less than or equal$) 0.27 ORb | 1 | |
Average U-factor $(less than or equal$) 0.25 ORb | 2 | ||
Average U-factor $(less than or equal$) 0.21 ORb | 3 | ||
Average U-factor $(less than or equal$) 0.18 | 4 | ||
Doors - Exterior | U-0.26 | 1 | |
Air Leakage | Tight | Tested to $(less than or equal$) 0.11 CFM50/Sq. Ft. of Building Shell (6-sided) (~1.5 ACH50) ORb | 1 |
Tighter | Tested to $(less than or equal$)0.07 CFM50/Sq. Ft. of Building Shell (6-sided) (~1.0 ACH50) ORb | 2 | |
Tightest | Tested to $(less than or equal$)0.03 CFM50/Sq. Ft. of Building Shell (6-sided) (~0.5 ACH50) | 3 | |
Mechanical Ventilation | Better Heat Recovery OR | Balanced ventilation with ECM fans and $(greater than or equal$)80% SRE and $(greater than or equal$)1.2 cfm/watt ORb | 3 |
Better Electrical Efficiency | Balanced ventilation with ECM fans and $(greater than or equal$)70% SRE, and $(greater than or equal$)2.0 cfm/watt | ||
Mechanical Ventilation Testing | Mechanical ventilation systems shall be tested and verified to provide the minimum ventilation flow rates required by Section R403.6. Testing shall be performed according to the ventilation equipment manufacturer's instructions, or by using a flow hood or box, flow grid, or other airflow measuring device at the mechanical ventilation fan's inlet terminals or grilles, outlet terminals or grilles, or in the connected ventilation ducts. | 1 | |
For SI: 1 foot = 304.8 mm.
RESNET Water Energy Rating Index compliant: http://www.resnet.us/professional/about/resnet_to_develop_water_efficiency_rating_system.
delete and replace R402.1.3 R-value computation.
Insulation material used in layers, such as framing cavity insulation, or continuous insulation Cavity insulation alone shall be used to determine compliance with the cavity insulation R-value requirements in Tables R402.1.1 and R402.1.3. Where cavity insulation is installed in multiple layers, the R-values of the cavity insulation layers shall be summed to compute the corresponding component R-value determine compliance with the cavity insulation R-value requirements. The manufacturer's settled R-value shall be used for blown insulation. Continuous insulation (ci) alone shall be used to determine compliance with the continuous insulation R-value requirements in Tables R402.1.1 and R402.1.3. Where continuous insulation is installed in multiple layers, the R-values of the continuous insulation layers shall be summed to determine compliance with the continuous insulation R-value requirements. Cavity insulation R-values shall not be used to determine compliance with the continuous insulation R-value requirements in Tables R402.1.1 and R402.1.3. Computed R-values shall not include an R-value for other building materials or air films. Where insulated siding is used for the purpose of complying with the continuous insulation requirements of Tables R402.1.1 and R402.1.3, the manufacturer's labeled R-value for insulated siding shall be reduced by R-0.6.
Average continuous insulation R-values across flat roofs meet the requirements of Tables R402.1.2.1 and R402.1.2.3
delete and replace R402.1.4 U-factor alternative.
An assembly with a U-factor equal to or less than that specified in Table R402.1.4 shall be permitted as an alternative to the R-values in Tables R402.1.2.1 and R402.1.2.3. The building must still comply with Tables R402.1.2.1, R402.1.2.2, and Table R402.1.2.3.
An assembly with a U-factor equal to or less than that specified in Table R402.1.4 shall be permitted as an alternative compliance method with no Table R402.1.2.3 points required, provided that (a) airtightness is less than or equal to 0.15 CFM50/Sq. Ft. of Building Shell (~2 ACH50) tested, and (b) the ventilation system complies with section R304.
Exception: The following are not required to comply with the airtightness limit or the balanced ventilation system and heat recovery efficiency requirements.
delete and replace TABLE R402.1.4
TABLE R402.1.4
EQUIVALENT U-FACTORS
FENESTRATION U-FACTOR | SKYLIGHT U-FACTOR | CEILING U-FACTOR | FRAME WALL U-FACTOR | MASS WALL U-b FACTOR | FLOOR U-FACTOR | BASEMENT WALL U-FACTOR | CRAWL SPACE WALL U-FACTOR | SLAB ON GRADE & UNHEATE D SLAB U-FACTOR & DEPTH |
0.30 | 0.41 | 0.020 | 0.044 | 0.060 | 0.027 | 0.39 | 0.39 | 0.05, 4 ft |
For SI: 1 foot = 304.8 mm.
delete and replace R402.1.5 Total UA alternative.
Where the total building thermal envelope UA, the sum of U-factor times assembly area, is less than or equal to the total UA resulting from multiplying the U-factors in Table R402.1.4 by the same assembly area as in the proposed building, the building shall be considered to be in compliance provided that (a) airtightness is less than or equal to 0.15 CFM50/Sq. Ft. of Building Shell (~2 ACH50) tested, and (b) the ventilation system is: balanced, complying with R304. The UA calculation shall be performed using a method consistent with the ASHRAE Handbook of Fundamentals and shall include the thermal bridging effects of framing materials.
Exception: The following are not required to comply with the airtightness limit (a) or the balanced ventilation system and heat recovery efficiency requirements (b).
delete and replace R402.1.6 Log homes.
Log homes shall comply by doing all of the following steps:
delete and replace TABLE R402.1.6
delete and replace R402.2.1 Ceilings with attic spaces.
Where Section R402.1.2 would require R-49 insulation in the ceiling, installing R-38 over the top of exterior walls where insulation is compressed in the eaves shall be deemed to satisfy the requirement for R-49 insulation provided that the balance of the ceiling is at R-49. Where Section R402.1 would require R-60 insulation in the ceiling, installing R-49 over the top of exterior walls where insulation is compressed in the eaves shall be deemed to satisfy the requirement for R-60 provided the balance of the ceiling is at R-60. This reduction shall not apply to the U-factor alternative approach in Section R402.1.4 and the total UA alternative in Section R402.1.5.
delete and replace R402.2.2 Ceilings without attic spaces (slopes).
Where Section R402.1.2 would require R-49 insulation in the ceiling, installing R-38 over the top of exterior walls where insulation is compressed in the eaves shall be deemed to satisfy the requirement for R-49 insulation provided that the balance of the ceiling is at R-49. Where Section R402.1 would require R-60 insulation in the ceiling, installing R-49 over the top of exterior walls where insulation is compressed in the eaves shall be deemed to satisfy the requirement for R-60 This reduction shall not apply to the U-factor alternative approach in Section R402.1.4 and the Total UA alternative in Section R402.1.5.
delete and replace R402.2.3 Eave baffle.
For air-permeable insulations in vented attics, a baffle shall be installed adjacent to soffit and eave vents. Baffles shall maintain a net free area opening equal to or greater than the net free area of the vent. The baffle shall extend over the top of the attic insulation. The baffle shall be permitted to be any solid material.
The baffle shall be installed to the outer edge of the exterior wall top plate so as to provide maximum space for attic insulation coverage over the top plate. Where soffit venting is not continuous, baffles shall be installed continuously to prevent ventilation air in the eave soffit from bypassing the baffle.
delete and replace R402.2.4 Access hatches and doors.
Access hatches and doors from conditioned spaces to unconditioned spaces such as attics and crawl spaces shall be weatherstripped and insulated to the same R-value required by Section R402 for the wall or ceiling in which they are installed. Access shall be provided to all equipment that prevents damaging or compressing the insulation. A wood-framed or equivalent baffle or retainer is required to be provided when loose-fill insulation is installed, the purpose of which is to prevent the loose-fill insulation from spilling into the living space when the attic access is opened, and to provide a permanent means of maintaining the installed R-value of the loose-fill insulation.
Exception: Vertical doors that provide access from conditioned to unconditioned spaces shall be permitted to meet the fenestration requirements of Table R402.1.2.1.
The reduction shall not apply to the total UA alternative in Section R402.1.5.
delete and replace R402.2.6 Steel-frame ceilings, walls and floors.
Steel-frame ceilings, walls, and floors shall comply with the U-factor requirements of Table R402.1.2.1. The calculation of the U-factor for steel-framed ceilings and walls in an envelope assembly shall be determined in accordance with AISI S250 as modified herein.
S250 calculation option for other than standard C-shape framing is permitted to be used.
delete TABLE R402.2.6
delete and replace R402.2.8 Floors.
Floor framing-cavity insulation shall be installed to maintain permanent contact with the underside of the subfloor decking.
Exception: The floor framing-cavity insulation shall be permitted to be in contact with the topside of sheathing or continuous insulation installed on the bottom side of floor framing where combined with insulation that meets or exceeds the minimum wood frame wall R-value in Table 402.1.2.1 and that extends from the bottom to the top of all perimeter floor framing members.
delete and replace R402.2.9 Basement walls.
Walls associated with conditioned basements shall be insulated from the top of the basement wall down to 10 feet (3048 mm) below grade or to the basement floor, whichever is less. Walls associated with unconditioned basements shall meet this requirement unless the floor overhead is insulated in accordance with Sections R402.1.2.1 and R402.2.8.
delete and replace R402.2.10 Slab-on-grade floors.
Slab-on-grade floors with a floor surface less than 12 inches (305 mm) below grade shall be insulated in accordance with Table R402.1.2.1. The insulation shall extend downward from the top of the slab on the outside or inside of the foundation wall. Insulation located below grade shall be extended the distance provided in Table R402.1.2.1 by any combination of vertical insulation, insulation extending under the slab or insulation extending out from the building. Insulation extending away from the building shall be protected by pavement or by not less than 10 inches (254 mm) of soil. The top edge of the insulation installed between the exterior wall and the edge of the interior slab shall be permitted to be cut at a 45-degree (0.79 rad) angle away from the exterior wall. Slab-edge insulation is not required in jurisdictions designated by the code official or authority having jurisdiction, where one exists, as having a very heavy termite infestation.
delete and replace R402.2.13 Sunroom and conditioned garage insulation.
Sunrooms enclosing conditioned space and conditioned garages shall meet the insulation requirements of this code.
Exception: For sunrooms and conditioned garages provided with thermal isolation, and enclosing conditioned space, the following exceptions to the insulation requirements of this code shall apply:
add R402.2.16 Building Science
Consider building science principles in all design and construction. Buildings should be designed and constructed recognizing principles behind moisture vapor control approaches for cold climates. Maintain the envelope assembly's ability to adequately dry in at least one direction by not installing low-perm vapor retarder materials (e.g., vapor barrier) on both sides of an assembly, seek to optimize the assembly's ability to dry, and limit the potential for wetting. (From Applied Building Technologies Group, LLC).
delete and replace R402.3 Fenestration.
In addition to the requirements of Section R402.1.2.1, fenestration shall comply with Sections R402.3.1 through R402.3.5.
delete and replace R402.3.2 Glazed fenestration SHGC.
An area-weighted average of fenestration products more than 50-percent glazed shall be permitted to satisfy the SHGC requirements.
Dynamic glazing shall be permitted to satisfy the SHGC requirements of Table R402.1.2.1 provided the ratio of the higher to lower labeled SHGC is greater than or equal to 2.4, and the dynamic glazing is automatically controlled to modulate the amount of solar gain into the space in multiple steps.
Dynamic glazing shall be considered separately from other fenestration, and area-weighted averaging with other fenestration that is not dynamic glazing shall not be permitted.
Exception: Dynamic glazing is not required to comply with this section when both the lower and higher labeled SHGC already comply with the requirements of Table R402.1.2.1.
delete and replace R402.3.3 Glazed fenestration exemption.
Up to 15 square feet (1.4 m) of glazed fenestration per dwelling unit shall be permitted to be
exempt from U-factor and SHGC requirements in Section R402.1.2.1. This exemption shall not apply
to the U-factor alternative approach in Section R402.1.4 and the Total UA alternative in Section R402.1.5.
delete and replace R402.3.4 Opaque door exemption.
delete and replace R402.3.5 Sunroom and conditioned garage fenestration.
Sunrooms and conditioned garages enclosing conditioned space shall meet the fenestration requirements of this code.
Exception: sunrooms and conditioned garages with thermal isolation and enclosing conditioned space, the fenestration U-factor shall not exceed 0.30 and the skylight U-factor shall not exceed 0.41.
New fenestration separating a sunroom or heated garage with thermal isolation from conditioned space shall comply with the building thermal envelope requirements of this code.
delete and replace R402.4 Air leakage.
The building thermal envelope shall be constructed to limit air leakage in accordance with the requirements of this Section.
delete and replace R402.4.1 Building thermal envelope.
The building thermal envelope shall comply with Sections R402.4.1.1 through R402.4.1.3. The sealing methods between dissimilar materials shall allow for differential expansion and contraction.
delete and replace R402.4.1.1 Installation.
The components of the building thermal envelope as listed in Table R402.4.1.1 shall be installed in accordance with the manufacturer's instructions and the criteria listed in Table R402.4.1.1, as applicable to the method of construction.
delete and replace TABLE R402.4.1.1
TABLE R402.4.1.1
AIR BARRIER, AIR SEALING AND INSULATION INSTALLATION
COMPONENT | AIR BARRIER CRITERIA | INSULATION INSTALLATION CRITERIA |
General conditions and appropriate materials for air barriers | A continuous, durable air barrier shall be installed in the building envelope. Breaks or joints in the air barrier shall be sealed. The air barrier should be continuous and be durably connected to all penetrations, | Air-permeable insulation shall not be used as a sealing material; when installed in vertical walls, sloped ceilings, and floors within the thermal envelope, it shall be enclosed on all six sides and in contact with a |
windows and other (structural) interruptions. Open-cell or closed-cell foam shall have a finished thickness greater than or equal to 5.5 in. or 1.5 in., respectively, to qualify as an air barrier unless the manufacturer indicates otherwise. If flexible air barriers are used, they shall be fully sealed at all seams and edges and supported in accordance with manufacturer's installation instructions. Flexible air barriers shall not be made of kraft paper, or other materials that are easily torn. If polyethylene is used, its thickness shall be greater than or equal to 6 mil. Materials meeting ASTM E2357 Standard Test Method for Determining Air Leakage of Air Barrier Assemblies are acceptable. | durable, air barrier. | |
Dropped ceilings/soffits | The air barrier in any dropped ceiling/soffit shall be aligned with (in contact with) the insulation and any gaps in the air barrier shall be sealed. Access openings, drop downstairs or knee wall doors to unconditioned attic spaces shall be sealed, insulated and gasketed. | The insulation in any dropped ceiling/soffit shall be aligned with (in contact with) the air barrier and shall be enclosed on five sides and in contact with a durable, interior air barrier. A top-side air barrier is not required in a flat attic. |
Framing junctions and cavities | The junction of the foundation and sill plate shall be sealed. The junction of the top plate and the top of exterior wall sheathing shall be sealed. Knee walls shall be air sealed. When part of the thermal envelope, knee wall insulation shall be enclosed on all six sides and in contact with a durable, interior air barrier. | Cavities within corners and headers of frame walls shall be insulated by completely filling the cavity with a material having a minimum thermal resistance of R-3 per inch. Exterior thermal envelope insulation for framed walls shall be installed in substantial contact and continuous alignment with the air barrier. Exterior thermal envelope insulation for framed walls shall be enclosed on all six sides and in contact with a durable, air barrier. |
Windows, skylights and doors | The space between window/door jambs and framing, and skylights and framing shall be sealed with minimally-expanding foam, caulk with backer rod and sealant as well as flexible membranes supported by or adhered to rigid air barrier material. | -- |
Rim joists | Rim joists shall include an exterior air barrier. Junctions of the foundation and sill plate, sill plate and rim band, and rim band and subfloor shall be sealed. When air permeable insulation is installed, a | Rim joists shall be insulated and air sealed so that the insulation maintains permanent contact with the exterior rim board.b |
windows and other (structural) interruptions. Open-cell or closed-cell foam shall have a finished thickness greater than or equal to 5.5 in. or 1.5 in., respectively, to qualify as an air barrier unless the manufacturer indicates otherwise. If flexible air barriers are used, they shall be fully sealed at all seams and edges and supported in accordance with manufacturer's installation instructions. Flexible air barriers shall not be made of kraft paper, or other materials that are easily torn. If polyethylene is used, its thickness shall be greater than or equal to 6 mil. Materials meeting ASTM E2357 Standard Test Method for Determining Air Leakage of Air Barrier Assemblies are acceptable. | durable, air barrier. | |
Dropped ceilings/soffits | The air barrier in any dropped ceiling/soffit shall be aligned with (in contact with) the insulation and any gaps in the air barrier shall be sealed. Access openings, drop downstairs or knee wall doors to unconditioned attic spaces shall be sealed, insulated and gasketed. | The insulation in any dropped ceiling/soffit shall be aligned with (in contact with) the air barrier and shall be enclosed on five sides and in contact with a durable, interior air barrier. A top-side air barrier is not required in a flat attic. |
(continued)
TABLE R402.4.1.1--continued
AIR BARRIER AND INSULATION INSTALLATION
COMPONENT | AIR BARRIER CRITERIA | INSULATION INSTALLATION CRITERIA |
Narrow cavities | Narrow cavities of 1 inch or less that are not able to be insulated shall be air sealed. | Batts in narrow cavities shall be cut to fit, or narrow cavities shall be filled by insulation that on installation readily conforms to the available cavity space. |
Garage separation | Air sealing shall be provided between the garage and conditioned spaces. | Insulated portions of the garage separation assembly shall be installed in accordance with Sections R303 and R402.2.7. and R402.2.7. |
Recessed lighting and appliances | Recessed light fixtures installed in the building thermal envelope shall be air sealed in accordance with Section R402.4.5. Recessed light fixtures and other appliances (speakers, exhaust fans, light shafts, etc.) installed in the building thermal envelope shall be ICAT (Insulation Contact and Air Tight) rated, airtight labeled (or "Washington State Approved") and sealed with a gasket or caulk between the housing and the interior wall or ceiling cover. Fixtures and appliances shall maintain required 1 clearances of not less than / inch from 2 combustible material and not less than 3 inches from insulation material, or as required by manufacturer's installation requirements. | Recessed light fixtures installed in the building thermal envelope shall be airtight and ICAT rated (ICAT-rated indicates Insulation Contact and Airtight and meets the IC and air tightness requirement), and shall be buried or surrounded with insulation. |
Plumbing and wiring | All holes created by wiring, plumbing or other penetrations in the air barrier assembly shall be air sealed. | Insulation shall be installed to fill the available space and surround wiring, plumbing, or other obstructions, unless the required R-value can be met by installing insulation and air barrier systems completely to the exterior side of the obstructions. Insulation shall be placed between the exterior of the wall assembly and pipes. Insulation should not be installed on the interior of the piping. Batt insulation shall be cut neatly to fit around wiring and plumbing in exterior walls, or insulation that on installation readily conforms to available space shall extend behind piping and wiring and shall be in full contact with all air barriers. |
Shower/tub on exterior wall | Exterior walls adjacent to showers and tubs shall have insulation filling any gaps or voids between tub or shower walls and unconditioned space. | Exterior walls adjacent to showers and tubs shall have a rigid, durable air barrier separating the exterior wall from the shower and tubs and be insulated. |
Electrical/phone box on exterior walls | The air barrier shall be installed behind electrical, or communication boxes or air-sealed boxes shall be installed. | Insulation completely fills voids between the box and exterior sheathing. |
delete and replace R402.4.1.2 Air Leakage Testing. The building or dwelling unit shall be tested and verified as having an air leakage rate not exceeding two (2) air changes per hour or 0.15 CFM50/Sq. Ft. Building Shell area of all six sides of the building. Testing shall be conducted in accordance with ANSI/RESNET/ICC 380, ASTM E779 or ASTM E1827 and reported at a pressure of 0.2 inches w.g. (50 Pascals). Multifamily buildings shall comply with CBES C402.4. Testing and verification shall be conducted by an applicable Building Performance Institutes (BPI) Professional, a Home Energy Rating System (HERS) Energy Rater, HERS Field Inspector, or a Vermont Department of Public Service approved air leakage tester. A written report of the results of the test shall be signed by the party conducting the test. Testing shall be performed at any time after creation of all penetrations of the building thermal envelope. During testing:
Mechanical ventilation shall be provided in accordance with Section M1505 of the International Residential Code or Section 403.3.2 of the International Mechanical Code, as applicable, or with other approved means of ventilation.
delete and replace R402.4.1.3 Reporting.
Air leakage testing shall be reported on the RBES Certificate in units of air changes per hour at 50 Pascals (ACH50) and CFM50/Sq. Ft. Building Shell area of all six sides of the building.
delete and replace R402.4.2 Fireplaces.
New wood-burning fireplaces shall have tight-fitting doors and outdoor combustion air. Where using tight-fitting doors on factory-built fireplaces listed and labeled in accordance with UL 127, the doors shall be tested and listed for the fireplace. Where using tight-fitting doors on masonry fireplaces, the doors shall be listed and labeled in accordance with UL 907 2019.
add R402.4.6 Electrical and communication outlet boxes (air-sealed boxes).
Electrical and communication outlet boxes installed in the building thermal envelope that are through or outside the building air barrier shall be sealed to limit air leakage between conditioned and unconditioned spaces. Electrical and communication outlet boxes shall be tested in accordance with NEMA OS 4, Requirements for Air-Sealed Boxes for Electrical and Communication Applications and shall have an air leakage rate of not greater than 2.0 cubic feet per minute (0.944 L/s) at a pressure differential of 1.57 psf (75 Pa). Electrical and communication outlet boxes shall be marked "NEMA OS 4" or "OS 4" in accordance with NEMA OS 4. Electrical and communication outlet boxes shall be installed per the manufacturer's instructions and with any supplied components required to achieve compliance with NEMA OS 4.
delete and replace R402.5 Maximum fenestration U-factor and SHGC ().
The area-weighted average maximum fenestration U-factor permitted using tradeoffs from Section R402.1.5 or R405 shall be 0.30 for vertical fenestration, and 0.41 for skylights.
add R402.7 Solar-ready zone.
add R402.7.1 General.
Solar-ready zone is required for Stretch Code but is optional for Base Code. Points are available for meeting the solar-ready zone requirements for Base Code.
For Stretch Code, new detached one- and two-family dwellings, and multiple single-family dwellings (townhouses) with not less than 600 square feet (55.74 m2) of roof area oriented between 110 and 270 degrees of true north shall comply with this Section.
Exceptions:
Multifamily buildings shall comply with CBES C402.5.
add R402.7.2 Construction document requirements for solar-ready zone.
Construction documents shall indicate the solar-ready zone where applicable.
add R402.7.3 Solar-ready zone area.
The total solar-ready zone area shall consist of an area not less than 300 square feet (27.87 m) per dwelling exclusive of mandatory access or setback areas. New multiple single-family dwellings (townhouses) three stories or less in height above grade plane and with a total floor area less than or equal to 2,000 square feet (185.8 m) per dwelling shall have a solar-ready zone area of not less than 150 square feet (13.94 m) per dwelling. The solar-ready zone area shall be not less than 40 percent of the roof area calculated as the horizontally projected gross roof area less the area covered by skylights, occupied roof decks, vegetative roof areas and mandatory access or set back areas as required by the International Fire Code. The solar-ready zone shall be composed of areas not less than 5 feet (1524 mm) in width and not less than 80 square feet (7.44 m) exclusive of access or required set back areas.
For ground-mounted systems, possible locations of the panels must be identified in the submitted construction documents and be supported by a solar site evaluation. At least one potential location must be identified in the construction documents for the future installation of the panels.
add R402.7.4 Obstructions.
Solar-ready zones shall consist of an area free from obstructions, including but not limited to vents, chimneys, and roof-mounted equipment.
add R402.7.5 Shading.
The solar-ready zone shall be set back from any existing or new permanently affixed object on the building or site that is located south, east or west of the solar zone a distance not less than two times the object's height above the nearest point on the roof surface. Such objects include, but are not limited to, taller portions of the building itself, parapets, chimneys, antennas, signage, rooftop equipment, trees, and roof plantings.
add R402.7.6 Capped roof penetration sleeve.
A capped roof penetration sleeve shall be provided adjacent to a solar-ready zone located on a roof slope of not greater than 1 unit vertical in 12 units horizontal (8-percent slope). The capped roof penetration sleeve shall be sized to accommodate the future photovoltaic system conduit, but shall have an inside diameter of not less than 11/4 inches (32 mm).
add R402.7.7 Roof load documentation.
The structural design loads for roof dead load and roof live load to support the solar system shall be clearly indicated on the construction documents.
add R402.7.8 Interconnection pathway.
Construction documents shall indicate pathways for routing of conduit (or plumbing for solar thermal systems) from the solar-ready zone to the electrical service panel or service hot water system. Alternatively, install two 1-inch minimum diameter EMT conduits from the main electrical panel location to the attic or other area easily accessible to the solar array's proposed location. Conduits for future solar installations are to be capped, airtight and labeled at both ends.
add R402.7.9 Electrical service reserved space.
The main electrical service panel shall have a reserved space to allow installation of a dual pole circuit breaker for future solar electric installation and shall be labeled "For Future Solar Electric." The reserved space shall be positioned at the opposite (load) end from the input feeder location or main circuit location. Note: this requirement is in addition to the electrical service reserved space for electric vehicle charging. This requirement is only for the building master panel and not individual dwelling unit panels in the case of multifamily buildings.
add R402.7.10 Electrical energy storage system-ready area.
The floor area of the electrical energy storage system-ready area shall be not less than 2 feet (610 mm) in one dimension and 4 feet (1219 mm) in another dimension and located in accordance with Section 1207 of the International Fire Code. The location and layout diagram of the electrical energy storage system-ready area shall be indicated on the construction documents.
add R402.7.11 Construction documentation certificate.
A permanent certificate, indicating the solar-ready zone and other requirements of this section, shall be posted near the electrical distribution panel, water heater or other conspicuous location by the builder or registered design professional.
add R402.8 Tiny houses.
Tiny Houses as defined in Chapter 2 must comply with the envelope, insulation and fenestration requirements below. All other code provisions are still required.
Tiny houses require the following:
* ceiling flat attic U-0.033 (R-30);
* ceiling slope U-0.04 (R-24);
* above grade walls U-0.08 (R-13);
* frame floors U-0.05 (R-21);
* basement/crawl space walls R-20 continuous (ci) or R13+10ci;
* slab on grade R-20 for 4' on edge or under, OR R-15,4'(edge) + R-15 (under entire slab);
* heated slab on grade R-20,4' (edge) + R-15 (under entire slab);
* windows U-0.27;
* doors U-0.37;
* air leakage 0.15 CFM50/Sq. Ft. of Building Shell (~2 ACH50);
* ducts inside thermal boundary.
Compliance with all other provisions of this code is required.
Exception: Mechanical ventilation system for tiny houses is not required to be a balanced ventilation system and may be exhaust-only.
delete and replace R403.1.1 Programmable thermostat.
The thermostat controlling the primary heating or cooling system of the dwelling unit shall be capable of controlling the heating and cooling system on a daily schedule to maintain different temperature set points at different times of the day and different days of the week. This thermostat shall include the capability to set back or temporarily operate the system to maintain zone temperatures down to 55°F (13°C) or up to 85°F (29°C). The thermostat shall initially be programmed by the manufacturer with a heating temperature set point no higher than 70°F (21°C) and a cooling temperature set point no lower than 78°F (26°C). Adjustments to these settings for elderly, disabled or those with special needs is permissible.
Exception: The following are allowed only where a 5-wire connection to thermostat location is provided:
delete R403.1.2 Heat pump supplementary heat.
add R403.1.2 Ductless heat pump supplementary heat.
Ductless heat pumps shall not have integrated supplementary electric-resistance heat other than that provided for frost control. See Section R404.4 for guidance on electric-resistance heating equipment other than heat pumps.
delete and replace R403.3 Ducts.
Ducts and air handlers for space conditioning shall be in accordance with Sections R403.3.1 through R403.3.2.
delete R403.3.1 Ducts located outside conditioned space.
add R403.3.1 Duct placement.
All ducts and air handlers shall be located within conditioned space. delete R403.3.3 Duct testing.
delete R403.3.4 Duct leakage
delete R403.3.5 Building cavities
delete R403.3.6 Ducts buried within ceiling insulation.
delete R403.3.7 Ducts located in conditioned space.
delete and replace R403.4 Mechanical system piping insulation (Mandatory).
Mechanical system piping designed to carry fluids above 105°F (41°C) or below 55°F (13°C) shall be located within the building thermal envelope and insulated to a minimum of R-4.
delete and replace R403.5.1.1 Circulation systems.
Where installed, heated water circulation systems shall be provided with a circulation pump. The system return pipe shall be a dedicated return pipe or a cold-water supply pipe. Gravity and thermosyphon circulation systems shall be prohibited. Controls for circulating hot water system pumps shall automatically turn off the pump when the water in the circulation loop is at the desired temperature and when there is no demand for hot water. The controls shall limit the temperature of the water entering the cold-water piping to not greater than 104°F (40°C).
delete and replace R403.5.3 Hot water pipe insulation ().
Insulation for service hot water pipe with a minimum thermal resistance (R-value) of R-4 shall be applied to the following:
Follow the mechanical ventilation requirements in R304.
delete R403.6.1 Heat or energy recovery ventilation.
delete R403.6.1 Whole-house mechanical ventilation system fan efficacy.
delete TABLE R403.6.1
delete and replace R403.8 Systems serving multiple dwelling units.
Systems serving multiple dwelling units shall comply with Sections C403 and C404 of the 2024 Vermont Commercial Building Energy Standards (CBES) in lieu of Section R403 but will not be subject to the additional requirements outlined in Tables C406.1.1 and Table 406.1.2.
delete and replace R403.10.1 Residential pools and permanent residential spas.
Where installed, the energy consumption of residential swimming pools and permanent residential spas shall be controlled in accordance with the requirements of APSP 15.
delete and replace R403.10.4 Covers.
Outdoor heated pools and outdoor permanent spas shall be provided with an insulated vaporretardant cover of at least R-12 or other approved vapor-retardant means.
Exception: Where more than 75 percent of the energy for heating, computed over an operation season of not fewer than 3 calendar months, is from site-recovered energy, such as from a heat pump or solar energy source, covers or other vapor-retardant means shall not be required.
delete and replace R404.1 Lighting equipment.
All permanently installed lighting fixtures, excluding kitchen appliance lighting fixtures, shall contain only high-efficacy lighting sources.
delete R404.1.1 Lighting equipment
add R404.1.1 Exterior lighting.
Exterior lighting for residential buildings shall comply with Sections C405.5 (Exterior Lighting Power Requirements) of the Vermont Commercial Building Energy Standards (CBES).
Exceptions:
delete and replace R404.1.2 Lighting equipment for multifamily spaces
Multifamily buildings three-stories or less with common areas, stairwells, vestibules, lobbies, parking garages, and exterior parking areas and drives must meet the lighting power density (LPD) specifications of the Vermont Commercial Building Energy Standards (CBES). For parking garages, see Section C405.3.2; for uncovered parking areas and drives, see Section C405.5.2.
add R404.1.3 Fuel gas lighting equipment.
Fuel gas lighting systems shall not be permitted.
add R404.1.44 Exterior lighting controls.
Where the total permanently installed exterior lighting power is greater than 30 watts, the permanently installed exterior lighting shall comply with the following
actions. Exception: Lighting serving multiple dwelling units.
automatically returns automatic control to its normal operation within 24 hours.
For multifamily buildings, follow C405.2.7 (Exterior Lighting Controls).
delete R404.2 Electric resistance heating equipment.
add R404.2 Electric heating equipment.
Heat pumps shall be certified cold-climate heat pumps only and shall have controls that, except during defrost, prevent supplementary electric heat operation where the heat pump compressor can meet the heating load.
Building heating with electric-resistance heating equipment is prohibited.
Exceptions:
Note: Buildings served by the Burlington Electric Department (BED) must also receive approval from BED before installing electric resistance heating equipment.
delete and replace R404.3 Electric vehicle charging.
One Electric Vehicle Charging - Level 2 Capable parking space or Electric Vehicle Charging - Level 2 EVSE is required for new construction based on Table R404.3.
Exception: Electric vehicle parking spaces are not required if one of the following conditions apply:
Parking spaces with electric vehicle supply equipment (EVSE) shall be marked for EV use only.
Exception: The number of parking spaces with EVSE that are marked for "EV use only" need not exceed the number of EV cars driven by occupants of the building. This exception does not reduce the number of EVSE spaces required, just the number that are marked for EV use only. delete and replace
TABLE R404.3 REQUIRED LEVEL 2 CAPABLE ELECTRIC VEHICLE CHARGING PARKING SPACES FOR ALL NEW BUILDINGS (BASE CODE and STRETCH CODE)
BUILDING/PARKING TYPE | MINIMUM REQUIRED NUMBER OF LEVEL 2 CAPABLE EV CHARGING PARKING SPACES |
Single Family Home or Multifamily Building | 1 per dwelling unit or the number of parking spaces provided, whichever is less |
Additional Parking Spaces | 25% of remaining parking spaces not utilized by dwelling units, or 40 spaces, whichever is less |
For multifamily building garage or covered parking, provide on electrical drawings the appropriate sized pathway to the building electrical room to accommodate a future electrical upgrade for Level 2 EVSE electric vehicle charging; provide adequate wall and floor space in the building electrical room for future EV charging related electrical equipment; provide the appropriate sized pathways to exterior on-grade surface parking spaces for future Level 2 EVSE electric vehicle charging; provide a line diagram on the electrical drawings demonstrating a pathway for future Level 2 EVSE electric vehicle charging. Quantity of future Level 2 EVSE electric vehicle charging stations shall be as required by Table R404.3. add R404.4 200 Amp Electrical Service. Each new building, except for individual multifamily units, shall be supplied with at least 200 amp electrical service in anticipation of increased electrical services that will need to be provided in the future. add R404.5 Dwelling electrical meter. Each residential unit and each dwelling unit located in a Group R-2 building shall have a separate electrical meter. Exception: Buildings where a majority of the living units serve tenants at or below 80 percent of area median income. add R404.6 Electrical transformers. Low-voltage dry-type distribution electric transformers shall meet the minimum efficiency requirements of Table R405.6 as tested and rated in accordance with the test procedure listed in DOE 10 CFR 431. The efficiency shall be verified through certification under an approved certification program or, where a certification program does not exist, the equipment efficiency ratings shall be supported by data furnished by the transformer manufacturer. Exception: The following transformers are exempt:
TABLE R405.6
MINIMUM NOMINAL EFFICIENCY LEVELS FOR 10 CFR 431 LOW-VOLTAGE DRY-TYPE DISTRIBUTION TRANSFORMERS
SINGLE-PHASE TRANSFORMERS | THREE-PHASE TRANSFORMERS | ||
a kVA | b Efficiency (%) | a kVA | b Efficiency (%) |
15 | 97.70 | 15 | 97.89 |
25 | 98.00 | 30 | 98.23 |
37.5 | 98.20 | 45 | 98.40 |
50 | 98.30 | 75 | 98.60 |
75 | 98.50 | 112.5 | 98.74 |
100 | 98.60 | 150 | 98.83 |
167 | 98.70 | 225 | 98.94 |
250 | 98.80 | 300 | 99.02 |
333 | 98.90 | 500 | 99.14 |
-- | -- | 750 | 99.23 |
-- | -- | 1000 | 99.28 |
delete and replace R405.2 Mandatory requirements.
Compliance with this section requires that the applicable provisions in Sections R401.3, R402, R403, R404, and Chapter 3 be met.
modify "SECTION R406 ENERGY RATING INDEX COMPLIANCE ALTERNATIVE" to "SECTION R406 ENERGY RATING INDEX / HOME ENERGY RATING SYSTEM COMPLIANCE ALTERNATIVE"
delete and replace R406.2 Mandatory requirements.
Compliance with this section requires that the applicable provisions in Sections R401.3, R402, R403 and R404 be met. The building thermal envelope shall be greater than or equal to levels of efficiency and solar heat gain coefficients in Table 402.1.2 of the 2009 International Energy Conservation Code for Climate Zone 6.
delete R406.4 ERI-based compliance.
TABLE R406.4
ERI/HERS COMPLIANCE FOR BASE CODE AND STRETCH CODE
BASE CODE | STRETCH CODE |
60 | 59 |
delete R406.6.3 Additional documentation.
add R406.6.3 Renewable Energy Certificate (REC) Documentation.
Where on-site renewable energy is included in the calculation of an ERI, one of the following forms of documentation shall be provided to the code official or authority having jurisdiction, where one exists:
add R406.6.4 Additional documentation.
The code official or authority having jurisdiction, where one exists shall be permitted to require the following documents:
delete and replace R407.2 Compliance
Compliance for Stretch Code shall be documented through either Section R402.1.2.1 "Package Plus Points Approach" or Section R406 "Energy Rating Index / Home Energy Rating System (HERS) Compliance Approach".
For both Base Code and Stretch Code compliance, in Section R402.1.2.1 "Package Plus Points Approach", the same standard package is used. Stretch Code then requires more Points than the Base Code. For ERI/HERS compliance, a lower HERS Index is required for Stretch Code than for Base Code.
delete R407.2.1 Package Plus Points Approach.
delete TABLE R407.2.1.1 INSULATION AND FENESTRATION REQUIREMENTS BY COMPONENT FOR STRETCH PACKAGES
delete R407.2.1.2 Required points by building size.
delete TABLE R407.2.1.2
delete R407.2.1.3 Points by Component.
delete TABLE R407.2.1.3
delete R407.2.2 ERI-based compliance for Stretch Code.
delete R407.3 Air Leakage Testing for Stretch Code.
delete R407.4 Electric vehicle charging
delete R407.5 Solar Ready Zone for Stretch Code.
In order to earn Points from Table 402.1.2.3, complete calculation Table 408.1.1 to summarize estimated embodied carbon emissions from insulation materials used in the project. The output metric for this measure shall be global warming potential (GWP) intensity, capturing insulation GWP per conditioned square foot of project area. To complete the basic calculation, project teams shall provide the following information for foundation, wall, and roof insulation materials:
Type III Product-specific Environmental Product Declaration (EPD)
Projects may substitute product-specific data for the default GWP value if the specified product has a lower reported GWP than the default value. Product-specific shall be substituted in Column G of the calculation Table 408.1.1. Substitution of default GWP values is only allowed when type III product-specific EPDs are sourced and noted in Column G. Projects shall use GWP values that include A1-A3 lifecycle stages, as documented in product-specific EPDs, with the exception of SPF and XPS products. For these products, the A5 and B1 values shall be included in the documented GWP value to account for the on-site and off gassing impact of blowing agents. Projects shall provide the EPDs declaration number in Column G.
TABLE R408.1.2
DEFAULT INSULATION GLOBAL WARMING POTENTIAL VALUES
Material | Default Global Warming Potential (kg CO2e /sq.m. |
Cellular glass - Aggregate | RSI-1) |
Cellulose - Densepack | 3.93b |
Cellulose - Blown/loosefill | -2.10 |
Cork - Board | -1.10 |
EPS/graphite - Board, unfaced, Type II - 15psi | -6.80 |
EPS/graphite - Board, unfaced, Type IX - 25psi, graphite | 2.80 |
EPS - Board, unfaced, Type I - 10psi | 3.40 |
EPS - Board, unfaced, Type II - 15psi | 2.80 |
EPS - Board, unfaced, Type IX - 25psi | 3.80 |
Fiberglass - Batt, unfaced | 4.80 |
Fiberglass - Blown/loosefill | 0.70 |
Fiberglass - Blown/spray | 1.00 |
Hemp - Batt | 1.93c |
HempCrete | -0.50 |
Mineral wool - Batt, unfaced | -3.00 |
Mineral wool - Blown | 1.70 |
Mineral wool - Board, unfaced, "light" density | 1.60 |
Mineral wool - Board, unfaced, "heavy" density | 3.30 |
Phenolic foam - Board | 8.10 |
Polyiso - Wall Board | 1.54d |
Polyiso - Roof Board | 4.10 |
SPF - Spray, open cell | 2.90 |
SPF - Spray, closed cell HFO | 1.40 |
SPF - Spray, high density HFO | 4.20 |
SPF - Spray, closed cell HFC | 4.90 |
SPF - Spray, high density HFC | 13.10 |
Straw - Panel | 17.00 |
Vacuum Insulated Panel | -6.50 |
Wood fiber - Board, unfaced, European | 7.40 |
Wood fiber - Board, unfaced, North America | -6.50 |
Wood fiber - Batt, unfaced | -10.30 |
Wool (Sheep) - Batt | -2.40 |
Wool (Sheep) - Loosefill | 1.00 |
XPS - Board, 25psi HFC | 0.80 |
XPS - Board, 25psi "Low GWP" (HFO/HFC) | 55.50 |
4.90 |
delete R501.2 Existing buildings.
add R501.2 General
Except as specified in this chapter, this code shall not be used to require the removal, alteration or abandonment of, nor prevent the continued use and maintenance of, an existing building or building system lawfully in existence at the time of adoption of this code. Unaltered portions of the existing building or building supply system shall not be required to comply with this code.
delete and replace R501.4 Compliance.
Additions, alterations, or changes of occupancy to, or relocation of, an existing building, building system or portion thereof shall comply with Section R502, R503, R504 or R505, respectively, in this code. Changes where unconditioned space is changed to conditioned space shall comply with Section R502.
delete and replace R502.1.1.1 Building envelope.
New building envelope assemblies that are part of the addition shall comply with Sections R402.1, R402.2, R402.3.1 through R402.3.5, and R402.4. Air leakage testing in accordance with Section R402.4.1.2 is not required for additions complying with this code based on the attributes of the addition alone. Where the existing building and the addition comply with this code as a single building, or where the building with the addition does not use more energy than the existing building, testing must be performed in accordance with Section R402.4.1.2 and an air leakage rate not exceeding three (3) air changes per hour at 50 Pascals (or 0.23 CFM50/Sq. Ft. building shell area, six sided) must be verified.
Exception: Where unconditioned space is changed to conditioned space, the building envelope of the addition shall comply where the UA, as determined in Section R402.1.5, of the existing building and the addition, and any alterations that are part of the project, is less than or equal to UA generated for the existing building.
delete and replace R503.1 General.
Alterations to any building or structure shall comply with the requirements of the code for new construction, without requiring the unaltered portions of the existing building or building system to comply with this code. Alterations shall be such that the existing building or structure is no less conforming to the provisions of this code than the existing building or structure was prior to the alteration.
add R406.4 ERI/HERS-Based Compliance for Base Code and Stretch Code.
Compliance based on an ERI analysis requires that the rated design be shown to have an ERI/HERS Index less than or equal to 54 for Base Code and less than or equal to 47 for Stretch Code when compared to the ERI reference design. Up to 5 ERI points can be earned with renewables. This includes all residential structures, including log homes. The ERI to be used to verify compliance is REM v16.3.3 or later or Ekotrope version 4.0 or later that is accredited by RESNET at https://www.resnet.us/providers/accredited-providers/hers-software-tools/. If the HERS Index scale is revised, the Department of Public Service may update these Index points.
Alterations shall not create an unsafe or hazardous condition or overload existing building systems. Alterations shall be such that the existing building or structure uses no more energy than the existing building or structure prior to the alteration. Alterations to existing buildings shall comply with Sections R503.1.1 through R503.1.4.
delete and replace R503.1.4 Lighting.
New lighting systems that are part of the alteration shall comply with Section R404.1.
Exception: Alterations that replace less than 10 percent of the luminaires in a space, provided that such alterations do not increase the installed interior lighting power.
delete and replace R505.2 General.
Any space that is converted to a dwelling unit or portion thereof from another use shall comply with this code.
Exception: Where the simulated performance option in Section R405 is used to comply with this section, the annual energy cost of the proposed design is permitted to be 110 percent of the annual energy cost otherwise allowed by Section R405.
REFERENCED STANDARDS
delete and replace the following referenced standards in Chapter 6 as follows:
31-004 Code Vt. R. 31-000-004-X
January 1, 2005 Secretary of State Rule Log #04-20
AMENDED:
October 1, 2011 Secretary of State Rule Log #11-032; March 1, 2015 Secretary of State Rule Log #14-046; September 1, 2020 Secretary of State Rule Log #19-072; July 1, 2024 Secretary of State Rule Log #23-018
These rules are adopted under 30 V.S.A. §51. This document shall be known and cited as the 2020 Vermont Residential Building Energy Standard Amendments. The 2015 Vermont Residential Building Energy Standards (First Printing: March 2015) published by International Code Council (ICC), Inc., as amended herein, are incorporated by reference and are available on the ICC website at: http://www.iccsafe.org.
STATUTORY AUTHORITY:
30 V.S.A. §51