If you have a skylight, chimney, plumbing vent, or another type of installation on your roof, then the feature will typically be surrounded by a layer of flashing. Flashing is an aluminum construction that is installed to create a waterproof barrier around roofing protrusions. The flashing is adhered in place with nails and formed around the chimney or vent to keep water from leaking around it. Unfortunately, the flashing can pull up and cause a leak to develop in your roof. If you notice this issue, then keep reading to learn how to repair the leak.
Use Silicone Caulk
Most flashing installations are sealed around seams and edges to keep water from seeping behind the sheets of aluminum. The sealing is completed with silicone caulk. This is particularly important in areas where step flashing is noted, like around the sides of your chimney. Strip flashing and drip edges should be sealed with the silicone as well.
There are several different types of silicone caulk you can buy. You want to look for a variety made for roofing. The caulk will be a high heat variety that is UV and crack resistant. While many roofing caulks are black to match shingles, you can find white and clear varieties if you want the sealant to blend in it a bit better.
Flashing sealants are available as well. While these sealants can be used around the seams of the aluminum flashing, the material is meant to adhere the flashing to the roof. It is weather resistant, but the roofing caulk material is made for exposed surfaces where the flashing adhesives and sealants are not.
You can use a caulk gun to release a bead of the sealant along the edge of the flashing. Make sure the bead is thick and comes into direct contact with the flashing to reduce leak issues.
Add A Patch
Sometimes flashing will become pitted and form large holes due to long term wear. This type of flashing should be replaced if it has deteriorated significantly. However, if there is a single medium to large sized hole or just a few smaller holes, then the flashing can be patched. You can use your silicone sealant or a bit or urethane roofing cement to fill in smaller holes. Urethane roofing cement is a good choice area where the flashing is flat. Specifically, the cement is more flexible than the caulk and it is also made to remain weather resistant against pooled water.
If you need to repair a large opening, then you can add a patch with a piece of aluminum flashing material. Cut the flashing so it is slightly larger than the hole. Use a wire brush or a piece of sand paper to lightly score or roughen the area around the hole. Place a thick bead of flashing adhesive around the opening and press the patch in the adhesive. Once the adhesive dries, use silicone caulk around the edge to seal the patch.
If you don't feel comfortable doing roof repairs on your own, contact a professional in your area.