Rooftop PV Systems: Updated NRCA Guidelines, New Code Requirements and Equivalent Service Life

A building or home owner who invests in a roof-mounted PV system is making a long term investment in renewable energy and is attempting to fix a portion or all of his or her electricity costs.  A successful long-term investment in rooftop solar energy not only requires a properly performing, long-term PV system, but also requires a roof system to perform properly for an equivalent period of time.

The tenets of successful roof systems include good design, quality materials, proper installation and continued maintenance.  Understanding the purpose of roof assembly components—for steep-slope and low-slope roof systems—is necessary for the longevity of roof-mounted PV systems.  NRCA’s guidelines for roof-mounted PV systems are based on these four tenets, and the expectation that the roof system and PV system should have equivalent service lives. The speaker will provide NRCA's updated technical recommendations and guidelines for roof-mounted PV systems.

Rooftop PV system designs are mandated to meet building code requirements—e.g., drainage, fire, wind, impact.  PV-specific requirements in the 2012 Editions of the International Building Code (IBC), International Residential Code (IRC) and International Fire Code (IFC) will be discussed and methods for practical solution to meet code requirements will be provided.  The 2012 IBC will have specific requirements for rooftop PV systems in the roofing chapter; the 2012 IRC will have specific requirements for PV systems installed on one- and two -family dwellings in its roofing chapter; and the IFC also will have new requirements for access to and on roof systems with PV installations.

Understanding how roof assemblies function, recognizing NRCA’s roof system enhancements, and following building code requirements as they relate to steep-slope, low-slope, new construction and reroofing will help ensure long lasting, reliable rooftop PV systems.