Why 60-foot standing seam panels pop and bang, and what can be done after install

The poster describes 2-inch seams at 16 inches on center, sliding clips and runs up to 60 linear feet. Drexel Metals says a 30-foot steel panel moves about a quarter inch over a 100-degree change, so a 60-foot run moves about half an inch. The Metal Construction Association says panel temperatures can swing more than 200 degrees F in a season, 150 in a day and 100 within minutes when clouds and cold rain hit a hot roof.

The noise starts when friction or a hidden restraint holds a panel until the stress breaks it loose. MCA's clip guide says the clip-to-panel interface should keep friction low, because friction makes oil canning and thermal noise worse. MBCI says each panel should be pinned at one end, eave or ridge, and float toward the other, and calls fastening both ends the more serious mistake. Drexel adds that eave, ridge, hip and valley details must allow for movement, that clips and fasteners should not be overtightened, and that dark colors move more.

After install, the checks are physical. Look for anything that pins a panel a second time, such as ridge or eave trim screwed through the pan, or flashing fastened to both the panel and the wall. On insulated decks, Berridge staff engineer Lisa Reimert told Metal Construction News that popping grows when clip screws pass through rigid foam with no plywood or furring, because the fastener cantilevers. Plywood over the foam gives the screws solid bearing.

Drexel says no practice removes popping entirely and that the sounds usually fade as a roof settles into its daily cycle. Installers can write that into the contract, along with the fixed-point location and clip type taken from the panel maker's manual.