Are You Up To Code?
Your ability to install rooftop solar systems that consistently meet your building department’s expectations rests on your understanding of your relationship to the various code makers and enforcers involved with your installation.
This knowledge can make the difference between passing and failing an inspection, and, equally important, help you maintain any roof warranties in place and reduce your long-term liability for the installation.
If you are a homeowner, you'll want to be sure your installation is fully up to code as well. Everybody benefits when we "do solar right." It never pays to cut corners when installing a solar system on your roof.
Wheel of Accountability
After extensively studying the relevant organizations, codes and guidelines that impact rooftop structures and waterproofing, Quick Mount PV created the Wheel of Accountability to help solar designers and installers better understand these important relationships and responsibilities.
The AHJ (Authority Having Jurisdiction) – typically the local building inspector – is at the center of the Wheel. The AHJ has the final say on your installation, as he interprets the building codes and best standards and practices as agreed upon and published by the agencies listed along the circumference of the wheel. The AHJ is empowered to act on behalf of any of the entities listed on the wheel to make sure that you have met their requirements.
The ICC, SMACNA, NRCA and ARMA help provide time-tested, best-practice guidelines for roofing buildings and other enclosed structures. These guidelines are published by the IBC, IRC, SBC and NFPA, and also in manuals compiled by the individual trade groups. These manuals are available for purchase in many places on the web.
The ICC and UL provide quality standards and testing methods to ensure product-manufacturing compliance. OSHA focuses exclusively on workplace safety and can shut down any job site or fine an installer for unsafe workplace practices.
The roofing manufacturer is also included in our Wheel of Accountability, as closely following their installation instructions is critical to maintaining the roof warranty, as well as limiting long-term liability exposure to the owner and contractor alike.
Here are some of the key players and relevant building codes in the Wheel of Accountability, with links to their websites:
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. Among the many roofing industry manuals ARMA publishes, “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 established the Center PV Taskforce to bridge the gap and 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 and metal roofs, and will be developing guidelines for steep slope roofs in 2014.
The Tile Roofing Institute is the recognized authority on best practice guidelines for tile roofing systems. The TRI has produced technical manuals on code language and preferred installation practices within all the major code bodies nationwide. TRI has played a major role in developing legislation of building codes and developed the first industry-based series installation guides for all 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 devoted to flashing details and exterior metals. They publish the "Architectural Sheet Metal Manual" on a regular basis. 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 contains details and specifications for the vast majority of situations requiring flashings.
We are asked frequently about Underwriters Laboratories, as it plays an important role in evaluating the electrical elements of a PV solar system. UL evaluates products, components, materials and systems for their compliance to specific requirements, and permits acceptable products to carry a UL certification mark, as long as they remain compliant with UL standards. UL evaluates products for compliance with specific safety requirements, but UL certification does not guarantee the product will perform acceptably or that it is safe under all conditions, such as when the product is misused. UL develops its standards to correlate with the requirements of model installation codes like the National Electrical Code.
UL is currently in the process of developing a new standard (to be called UL2703) which, when finalized, will directly affect solar mounting products such as ours. This draft standard addresses the grounding of any metal surface under a PV array including flashings and mounting hardware. This proposed standard is currently being evaluated by industry subject matter experts. We will closely monitor the development of UL2703 and update this information once the standard is finalized.
The International Code Council (ICC) was established in 1994 as a nonprofit organization dedicated to developing a single set of comprehensive and coordinated national model construction codes out of the three regional codes established early in the 20th century by ICC founders Building Officials and Code Administrators International, Inc. (BOCA), International Conference of Building Officials (ICBO), and Southern Building Code Congress International, Inc. (SBCCI).
The National Fire Prevention Association is the world's leading advocate of fire prevention and an authoritative source on public safety. The NFPA develops, publishes, and disseminates more than 300 consensus codes and standards intended to minimize the possibility and effects of fire and other risks.
In construction, the Authority Having Jurisdiction (AHJ) is the governmental agency or sub-agency that regulates the construction process. In most cases, this is the municipality in which the building is located. Codes
All 50 states and the District of Columbia have adopted the International Building Code (IBC) and International Residential Code as models for their own State Building Codes (SBC). The IBC governs new construction in residential buildings four or more stories high. Amendments vary from state to state based on issues specific to regional and local conditions.
The International Residential Code (IRC), adopted in 46 states and the District of Columbia, creates minimum regulations for one- and two-family dwellings of three stories or less.
These "model" codes form the framework for local fire, building, housing, property maintenance, plumbing, electrical, energy, and mechanical codes.
Below are some of the building codes that apply to the installation of rooftop mounts and PV systems.
The Authority Having Jurisdiction will almost certainly base their local requirements on some version of the International Building Code. Here are a few paragraphs on waterproofing:
- 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 offers guidance on solar systems and reaffirms the importance of following the roofing manufacturer’s instructions on every installation.
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.
- R905.2.8.5 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 International Business Code (IBC), 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).