The skylight unit and the curb-to-roof connection are separate parts of the weather barrier. Dirt at step flashing, a damaged glazing seal, or loose membrane flashing can each produce a similar ceiling stain.

What to check first

  • Clear debris without blocking designed drainage channels.
  • Inspect operable skylight seals and closure.
  • Use the skylight manufacturer's repair guidance when replacing gaskets or glazing.

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.

Watch the field examples

These archive demonstrations show individual projects. Use the current guidance above and Bergstrom’s published instructions if an older video shows a different product or method. Torch work shown in installation videos is professional work.

From the project archive

Project detail: Leaking Skylights: Glazing Seals and Curb Flashing
Historical project photo · Flat Roof Doctor
Project detail: Leaking Skylights: Glazing Seals and Curb Flashing
Historical project photo · Flat Roof Doctor
Skylight Repairs - Sometimes the skylight will leak between the dome and frame.
Historical project photo · Flat Roof Doctor

Product reference: Bergstrom Industries’ published knowledge catalog. Follow the latest product label and safety information. Historical project examples are educational and are not a specification for every roof.