Are You Up To Code?
Wheel of Accountability
The ability to install rooftop solar systems that consistently meet waterproofing code requirements rests on understanding the relationship between code, roofing manufacturers, and best practice guidelines. This knowledge can make the difference between passing and failing an inspection, and helps maintain any roof warranties as well as reduce long-term liability.
Quick Mount PV created the Wheel of Accountability to help solar designers and installers better understand the relationships between relevant codes, standards and best practices, guidelines that impact rooftop structures and waterproofing.
The AHJ (Authority Having Jurisdiction) – typically the local building department – is at the center of the Wheel. The AHJ has final say on how rooftop solar systems will be installed. The AHJ is empowered to interpret codes and standards and enact special requirements that address climatic, geological, seismological, or topographical conditions unique to that area.
OSHA establishes workplace safety requirements and can shut down any job site or fine an installer for unsafe workplace practices.
The National Fire Protection Association (NFPA) publishes the National Electric Code that governs equipment-grounding requirements for PV systems. UL develops the UL 2703 standard for rack mounted PV systems which outlines the proper methods for ensuring a reliable equipment ground for the modules and rack to minimize the potential for shock or fire hazard in the event of an accidental fault. Building codes are developed by the International Code Council (ICC) – they publish the International Building Code and International Residential Codes, which are used as the basis for almost every State Building Code. Building codes require that all roof penetrations be waterproofed with flashing that complies with the roofing manufacturer requirement. The NRCA and ARMA publish installation guidelines used by the overwhelming majority of shingle manufactures, and the Tile Roofing Institute publish flashing guidelines used by the vast majority of tile manufacturers.
The ICC offers testing and certification for roof attachments and many Quick Mount PV products have the ICC Evaluation Service Report certification.
The roofing manufacturer is included in the Wheel of Accountability, as building code establishes the manufacturer as the entity that determines proper flashing procedure. It is necessary to follow roofing manufacturer flashing installation instructions to comply with code and maintain the roof warranty
Key Players and Building Codes
Below are some of the key players and relevant building codes in the Wheel of Accountability.
National Roofing Contractors Association roofing manuals provide time-tested, best-practice guidelines and technical information concerning the materials, design and installation of roof systems. The NRCA derives its information from knowledgeable, practicing roofing contractors located throughout the U.S.
The Asphalt Roofing Manufacturers Association represents about 95% of North America's asphalt (bituminous-based) roofing manufacturing companies and their raw material suppliers. ARMA spearheads industry research and development and provides information on modern asphalt roofing materials and practices to building and code officials, regulatory agencies and allied trade groups.. ARMA's “The Asphalt Roofing Residential Manual - Design and Application Methods” is required for anyone who wants to know how to work on a roof without voiding its warranty.
The Center for Environmental Innovation in Roofing (CEIR) established the CEIR PV Taskforce to increase communication between the roofing and solar industries. The Taskforce aims to drive higher quality combined solar energy roofing systems through best practices and industry standards. The Center PV Taskforce has developed PV installation guidelines for low slope membrane roofs, low slope metal roofs, and steep slope shingle roofs.
The Tile Roofing Institute is the recognized authority on best practice guidelines for flashing and waterproofing on tile roofing systems. The TRI publishes installation guides for tile roofs and flashing methods for cold and warm weather climatic regions. The TRI trains roofing installers, inspectors and industry professionals on proper, code-approved methods for installing concrete and clay tile roofs. TRI is dedicated to growing the tile roofing market through technical expertise, training, and building awareness for the many benefits of tile.
The Sheet Metal and Air-conditioning Contractors National Association, is dedicated to flashing details and exterior metals and publishes the "Architectural Sheet Metal Manual". First published in 1965, the manual addresses all aspects of flashing and building envelope metals, with an emphasis on preventing building moisture intrusion. The manual is updated on a regular basis and contains details and specifications for the vast majority of situations requiring flashings.
Underwriters Laboratory develops widely accepted standards for modules, inverters, and PV racking systems. The UL 2703 standard establishes requirements for bonding and grounding, corrosion, structural capacity, and fire classification for PV racking systems UL certification does not guarantee the product will perform acceptably, but a properly designed and installed UL 2703 listed racking system should considerably reduce the potential of safety problems that can plague poor quality systems.
The International Code Council (ICC) is a nonprofit organization dedicated to developing building codes that help permitting officials and inspectors validate the safety of the systems installed on residential and commercial structures.
The 2012 International Fire Code introduced spacing "setbacks" for PV arrays from the ridge, rakes, hips and valleys, and other obstacles such as gas vents, chimneys, access hatches, and skylights. These new setback requirements are intended to provide ventilation access and pathways for firefighters to clear smoke and noxious gasses in structures during a fire event. These setback requirements have resulted in less space for solar systems on residential structures, and are being re-evaluated by fire and solar industry subject matter experts to determine if the setback requirements can be reduced to allow more solar panels on a home.
The IFC on the ICC website
The National Electric Code (NEC) is developed by the National Fire Protection Association and serves as the benchmark code for safe electrical design, installation, and inspection to protect people and property from shock and fire hazards. The NEC outlines proper wiring and grounding of PV systems.
THE NEC on the NFPA website
In construction, the Authority Having Jurisdiction (AHJ) is the governmental agency or sub-agency that regulates the construction process. In most cases, the AHJ is the municipality in which the structure is located. The AHJ’s building department has permitting officials and inspectors who evaluate system design and installation to ensure solar systems meet the applicable building, fire, electrical, and/or plumbing codes.
Almost every state utilizes the International Building Code (IBC) and International Residential Code (IRC) as the basis for their own State Building Codes (SBC). The IRC governs new construction in single or two family structures of three stories or less and the IBC governs all other structures. Amendments vary from state to state based on issues specific to regional and local conditions.
State Building Codes form the framework for local fire, building, housing, property maintenance, plumbing, electrical, energy, and mechanical codes.
The International Building Code addresses waterproofing of penetrations in the following sections:
- 1503.2. Flashing shall be installed in such a manner so as to prevent moisture entering the wall and roof through joints in copings, through moisture-permeable materials and at intersections with parapet walls and other penetrations through the roof plane
- 1503.2.1 Flashing shall be installed at wall and roof intersections, at gutters, wherever there is a change in roof slope or direction; and around roof openings. Where flashing is of metal, the metal shall be corrosion-resistant with a thickness of not less than 0.019 inch.
- 1506.1 The requirements set forth in this section apply to the application of roof-covering materials specified herein. Roof coverings shall be applied in accordance with this chapter and the manufacturer's installation instructions. Installation of roof coverings shall apply to the applicable provisions of Section 1507.
- 1506.2 Compatibility of Materials. Roofs and roof coverings shall be of materials that are compatible with each other and with the building or structure to which the materials are applied.
- 1506.4 Product Identification. Roof covering materials shall be delivered in packages bearing the manufacturers' identifying marks and approved testing agency labels required in accordance with Section 1505 Bulk shipments of materials shall be accompanied with the same information issued in the form of a certificate or on a bill of lading by the manufacturer.
- 1507.2.9 Flashings. Flashings for asphalt shingles shall comply with this section. Flashing shall be applied in accordance with this section and the asphalt shingle manufacturer's printed instructions.
- 1507.8.7 At the juncture of the roof and vertical surfaces, flashing and counter flashing shall be provided in accordance with the manufacturer's written installation instructions, and where of metal, shall not be less than 0.019 inch (0.48mm) (No, 26 galvanized sheet gage) corrosion-resistant metal.
The International Residential Code addresses waterproofing of penetrations in the following sections:
Chapter 23 Solar Systems
- M2301.2 Installation: Installation of solar energy systems shall comply with Sections M2301.2.1 through M2301.2.9.
- M2301.2.2 Roof-mounted collectors: The roof shall be constructed to support the loads imposed by roof-mounted solar collectors. Roof-mounted solar collectors that serve as a roof covering shall conform to the requirements for roof coverings in Chapter 9 of this code. Where mounted on or above roof coverings, the collectors and supporting structure shall be constructed of noncombustible materials or fire-retardant-treated wood equivalent to that required for the roof construction.
- M2301.2.7 Roof and wall penetrations: Roof and wall penetrations shall be flashed and sealed in accordance with Chapter 9 of this code to prevent entry of water, rodents and insects.
- R901.1 Scope: The provisions of this chapter shall govern the design, materials, construction and quality of roof assemblies.
- R903.1 General: Roof decks shall be covered with approved roof coverings secured to the building or structure in accordance with the provisions of this chapter. Roof assemblies shall be designed and installed in accordance with this code and the approved manufacturer's installation instructions such that the roof assembly shall serve to protect the building or structure.
- R903.2 Flashing: Flashings shall be installed in a manner that prevents moisture from entering the wall and roof through joints in copings, through moisture-permeable materials and at intersections with parapet walls and other penetrations through the roof plane.
- R903.2.1 Locations: Flashings shall be installed at wall and roof slope or direction around roof openings. Where flashing is of metal, the metal shall be corrosion-resistant with the thickness of no less than 0,019 inch (0.5 mm) (No. 26 galvanized sheet).
- R905.2.8 Flashing: Flashing for asphalt shingles shall comply with this section.
- R905.2.8.1 Base and cap flashing (p441). Base and cap flashing shall be installed in accordance with manufacturer’s instructions.
- R905.2.8.4 Other Flashing: Flashing against a vertical front wall, as well as soil stack, vent pipe and chimney flashing, shall be applied according to the asphalt shingle manufacturer's printed instructions.
State Building Codes typically adopt language in whole or in part from the IBC and IRC, as with the California Building Standards Code of Regulations, Title 24, Section 1503, which advises the use of appropriate flashing in key locations for weather proofing:
- In Section 1503.2 "Flashings shall be installed in such a manner so as to prevent moisture from entering the wall and roof through joints in copings, through moisture-permeable materials, and at intersections with parapet walls and other penetrations through the roof plane."
- In Section 1503.2.1 Flashings shall be installed at wall and roof intersections; wherever there is a change in roof slope or direction; and around roof openings. Where flashing is of metal, the metal shall be corrosion-resistant with a thickness of not less than 0.019 inch (No. 26 galvanized steel).