Skylights and Skylight Leaks

What Is Skylights and Skylight Leaks?

A skylight is a glazed unit set in a curb or deck-mounted frame, waterproofed by a manufacturer flashing kit that laces into the surrounding shingles. When one 'leaks,' there are three distinct failure modes to separate. Flashing failure — aged, improperly layered, or sealant-patched flashing — is the true roof leak, and it is the most common. Unit failure — a cracked dome, a failed insulated-glass seal that fogs between panes, or perished gasket seals — is a window problem on the roof. Condensation — interior moisture hitting cold glass, common over kitchens and baths — is a ventilation problem that drips convincingly without any breach. The durable economics: skylights have service lives comparable to or shorter than the roof around them, so reusing an old skylight during a reroof is a false saving — the flashing must be redone anyway, and a unit that fails two years later requires disturbing the new roof. Hail commonly cracks acrylic domes, making skylights routine line items on hail claims.

Important Distinction

Note: Not every wet skylight is a leak: condensation on cold glass and failed insulated-glass seals (fogging between panes) both mimic roof leaks and have different fixes.

Also Known As

These are the search terms and phrases that commonly refer to this topic, so you can find it however you describe it.