Flashing

Flashing is a weatherproof metal or rubber component installed at every point where solar racking hardware penetrates the roof surface. Its purpose is to create a watertight seal that prevents leaks around the bolt holes used to secure the mounting system to the roof structure.

Proper flashing is one of the most critical aspects of a quality solar installation. Each roof attachment point involves drilling a lag bolt through the roofing material into the rafter below, and the flashing slides under the shingles (or sits on top of tile or metal roofing) to redirect water away from the penetration. Common flashing types include L-foot flashing for asphalt shingle roofs, tile hooks for tile roofs, and standing seam clamps for metal roofs (which don’t actually penetrate the roof). High-quality flashings are typically made of aluminum or stainless steel with an integrated rubber or EPDM gasket for a waterproof seal. A properly installed flashing should maintain a watertight seal for 25+ years — matching the lifespan of the solar system. Leaks from solar installations are rare when qualified installers use proper flashing techniques, but they can occur with poor workmanship, which is why choosing a reputable installer with strong workmanship warranties is important.