What are foam closure strips on a metal roof?
Short answer. Foam closure strips are profile-matched foam strips that fill the gaps between ribbed or corrugated metal panels and the trim at the eaves, ridges and walls. They block wind-driven rain, insects, birds and debris, and vented versions let air move at the ridge while still keeping weather out.
Inside vs outside closures
- Inside closures: shaped to fill the space under the panel, between the panel and the eave trim or deck. Used at eaves.
- Outside closures: shaped to fill the space on top of the panel, between the panel ribs and the ridge cap or wall flashing. Used at ridges, hips and walls.
Profile matching
Closures are cut to the exact rib shape of a specific panel. A closure for one panel leaves gaps on another even if the two look similar, so order closures with the panels.
Solid vs vented
Solid closures seal completely. Vented closures include a breathable mesh or baffle so a ridge can exhaust attic air while still stopping rain and insects. If your attic depends on ridge exhaust, the ridge closure must be vented and paired with soffit intake.
Installation tips
- Seal both sides of the closure with butyl tape for a watertight joint.
- Position eave closures at the panel's lower edge so screws pass through the closure area.
- Set outside closures where the manufacturer details them under the ridge cap, not hanging out.
- Do not crush closures flat by overdriving fasteners.
When they fail
Sun-exposed foam can crumble over time, and birds and wasps pick at it. Missing or deteriorated closures show up as daylight under ridge caps, nesting at eaves, and wet spots after wind-driven rain. Replacing them is a manageable repair.