Skylight leaking? What to check before assuming it needs replacing

A leaking skylight doesn't automatically mean a new unit. Most of the leaks Paul finds around skylights come down to failed flashing or perished sealant around the frame — both repairable — rather than the skylight itself being faulty.

Signs it's likely flashing or sealant, not the unit

• The leak only happens during wind-driven rain: A gap in the flashing or a shrunk sealant bead only lets water through when it's being pushed sideways, not in calm rain.
• You can see a gap or gap where sealant has dried and pulled away: Perished sealant around the frame is a common, straightforward fix.
• The stain or drip traces back to the edge of the skylight, not the glass itself: Water tracking in along the frame points to the seal, not the unit.

Signs it might be the skylight itself

• Cracking or hazing in the glazing: Visible cracks or persistent cloudiness in the dome or panel itself isn't a sealant problem.
• Condensation forming even in dry weather: This can point to a failed seal on the unit itself, not just the surrounding flashing.
• Leaks that keep coming back after resealing: If flashing repairs haven't held, the curb or frame underneath may have deteriorated.

What you can check from inside

1. Look for staining or damp patches on the ceiling around the skylight after rain.
2. Check whether the leak lines up with windy weather specifically, or happens in any rain.
3. Note if it's a new problem or one that's returned after a previous repair.

What Paul recommends

Most skylight leaks are a flashing or sealant fix, not a full replacement — but the two can look identical from inside the house. Paul offers a free on-site inspection to check the flashing, seal, and glazing before recommending anything, with a clear price before work starts.