Penetrations for small pipes and ducts should be flashed with standard metal roof pipe flashing (a flexible boot and a metal-backed sealing flange). For larger penetrations, a curb is attached to the roof to close the perimeter of the opening.
Penetrations for small pipes and ducts should be flashed with standard metal roof pipe flashing (a flexible boot and a metal-backed sealing flange). For larger penetrations, a curb is attached to the roof to close the perimeter of the opening.