Standing-seam metal roofs present their own challenges for installing PV arrays, as it isn’t possible to flash penetrations on existing metal roofs without replacing large sections of roofing material. S-5!’s PV Kit offers nonpenetrating clamps attached with set-screws, along with PV mounting clips, for dozens of standing-seam profiles. Regardless of the array attachment, the metal roof itself must be sufficiently fastened to the structure, as the PV array adds more uplift force and weight.
An option for standing-seam roofs is the ACECLAMP JR, which, instead of using set screws to attach to the metal seams, uses a 1-inch clamp bar, which is set from the clamp’s top, rather than its side.
VarioBracket (left) S-5! and CorruBracket (right) are attachment points made specifically for metal roofs with exposed fasteners. [Courtesy S-5!]
Exposed fastener (face-fastened) metal pan, also called corrugated metal, barn tin, or 5-V tin, is another common roofing material that poses challenges for PV arrays. Flashed brackets aren’t available for this roofing material. However, because the hundreds of fasteners used to attach the roofing material to the structure also are not flashed, it is generally accepted that PV attachment points can be unflashed as well. Second, exposed-fastener metal roofs come in a wide variety of profiles. Mounting systems for face-fastened metal roofing include DPW Solar’s corrugated mounting bridge, which comes with pre-applied butyl mastic sealant and is available in different profiles to match the roof profile. S-5!’s VarioBracket is a mounting bracket designed to adjust to any profile with a trapezoidal shape. Ejot, Schletter, and SnapNrack also provide special corrugated roof saddle-mount attachments.
DPW’s Corrugated Mounting Bridges are customized to fit the roofing material’s specific profile. [Courtesy DPW]
Schletter’s corrugated roofing solution—the FixE Eternit. [Courtesy Schletter]