Standing seam metal roof flashing details are installed at the intersections and terminations of the metal roofing system to seal the roof and prevent water from entering the roofing system. There are a couple of key types of flashing, or trim, that are used to seal each part of the metal roofing system.
The first type of flashing detail you should be aware of is the ridge cap.
Ridge caps provide a seal at the top of the roof line where the metal panels meet and prevent moisture accumulation and divert water.
The ridge cap is used to strengthen and seal the standing seam panels. Ridge caps are especially important because of their placement as they keep water out, but they also help provide a barrier for pests.
Ideally, ridge caps are end lapped 4-6 inches with the end laps installed away from the prevailing wind.
At the other end of the roofing system, eave trim is installed at the lowest point of the roof and is used to direct rain away from the roof fascia. This is the piece of trim that serves as the termination of the roof panel at the wall. The best practice is to install eave trim before installing the metal roof panels.
Rake trim, or gable trim, is a flashing detail piece that is installed along the roofline on the sloped sides of the roof. Unlike eave trim, rake trim is installed over the roof panel and along the wall.
In addition to ridge caps, eave trim, and rake trim, flashing should also be installed around any breaks in the roof surface like vents and skylights.
Want to learn more about metal roofing and standing seam roofing? The Residential Metal Roofing Guide explains the most common types of residential roofing substrates, coatings, warranties, and panel options. Click the link below to download your copy!