Do You Need an Air Gap under a Metal Roof?

Yes, we always create a ventilated air gap under every metal roof installation. This is a critical step because metal panels conduct heat rapidly and are prone to forming condensation on their undersides when temperatures drop.

We use either vertical battens or a dimpled mat to maintain a ventilation cavity of at least 1 inch. This design allows for consistent airflow from the soffit to the ridge, which expels moisture before it has a chance to damage your roof sheathing.

Failing to include this air gap is a common installation mistake. When metal panels are fastened directly to the deck without separation, trapped humidity can lead to:

• Rust forming on the back of the metal panels.
• Rot developing silently in the plywood roof deck.
• Structural decay over time due to persistent moisture.

If you are concerned about your current roof, you can check for rust lines along fasteners in the attic or look for condensation on the underside of the panels on cold mornings. As a Trusted Roofing Contractor with over two decades of local experience, we ensure these technical details are handled correctly to protect your home’s future.

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