Why a Skylight Leaks: Work through the Possible Entry Points

What to check first

• Note whether moisture follows rain or indoor humidity conditions.
• Inspect the unit above the flashing line.
• Check the roof-to-curb transition for a separate defect.

Identify which part of the skylight leaks

1. Separate unit problems from roof problems

   Check the glazing, gasket, frame, curb, and membrane connection as distinct details. Interior condensation can also produce moisture without a roof leak.

2. Protect the glazing and drainage paths

   Do not cover weep openings. Verify whether the glazing is glass or plastic before choosing a cleaner or product; aggressive solvents can damage some plastics.

3. Choose a compatible repair or replacement

   Turbo Poly Seal must not be applied directly to glass. Bergstrom identifies Super Silicone Seal for suitable glass repairs. A damaged frame or glazing unit may require replacement rather than another patch.

From the project archive