Leaks begin when the seal on your skylight has failed.
Skylights are popular with homeowners for the added natural light they bring into rooms. They are not so popular, though, when they begin to leak. This is a common problem with skylights as the watertight seal used during installation can degrade over time or become damaged in a storm. You can easily fix a leaking skylight. The most important part of the job is identifying which of the two areas of the skylight assembly is leaking. It may be both, but is usually only one.
Instructions
Determine the Location of the Leak
1. Set your ladder against your house so you can easily access your skylight to perform a water test to locate the leaks. Have a helper hold the ladder steady as you climb up to the roof. Once on the roof, have the helper hand you the garden hose.
If you're working more than one story above the ground, tie a piece of rope to the hose. Rather than carry the hose as you climb the ladder, hold onto the rope. Once you're upon the roof, pull up the hose.
2. Run water over the glass of the skylight first to see if the seal between the glass and the frame is leaking. Have a second helper inside--where they can see the skylight--tell you if water's leaking in. Make sure the helper dries off any water that leaks inside the house with a clean towel before testing the next seal on the skylight.
3. Run water over the flashing between the skylight and the roof shingles. The flashing is the smooth metal sheet attached to the skylight frame and lays over the top of the shingles. This allows water to run off the skylight and onto the roof. Have your helper inside spot any leaks during this test and to dry off any water that may leak through.
Repair the Seal between the Skylight Glass and Frame
4. Clean the glass of the skylight with glass cleaner and towels. Pay particular attention to where the glass meets the frame and remove any dirt or debris from that seam.
5. Load a cartridge of marine grade silicone caulk into your caulk gun. Marine grade is recommended as it is the most reliably waterproof standard on the market. Alternatively, you can use any silicone caulk that's clearly labeled as "waterproof."
6. Place a continuous bead of caulk into the seam between the glass and the frame of the skylight. Be careful to wipe off any excess caulk from the glass with a damp paper towel.
Repair the Seal between the Flashing and the Roof
7. Slide a thin metal paint scraper between the flashing and the shingles. Pull the scraper all the way around the flashing to completely break the seal on the old caulking. If your flashing has been placed beneath the shingles (as some styles allow), use the claw end of a hammer to pry up the shingles to access the flashing.
8. Pry up gently on the flashing and remove the old caulking by pulling it out of place with your fingers.
9. Clean between the flashing and the roof or shingles by using a paint brush to sweep away any debris between the two.
10. Add a cartridge of silicone caulk (marine-grade works best, but any waterproof caulk will do) into your caulk gun.
11. Apply a continuous bead of caulk under the flashing, near its edge, and press down the flashing. If your flashing was covered by shingles, reinstall the shingles. Caulk over each nail hole as you place the material.
Tags: silicone caulk, bead caulk, between glass, between glass frame, caulk into
