Seal A Leaking Flat Roof

Clean and dry the area you wish to apply flex seal.

Seal a leaking flat roof.

Apply an epdm primer and when touch dry add self adhesive rubber tape 3 around malleable flashing covering the hole. Do a small area at a time to really pinpoint the cause of the leak. Feathering or tapering the edges of thick but sound roof coating. This can be done by pouring a small amount of water over the area you suspect the hole in your roof is located and checking for the leak underneath.

For a gap of 1 inch or less caulking or sealant is the best method of repair. Step 2 fill a caulking gun with a watertight polyurethane or oil based sealant and hold it at an angle to insert the product directly into the gap. When the membrane is completely dry apply the appropriate roof repair material such as roof cement tar or peel and stick patch. Be sure to check any areas where the roof comes to a juncture or where there are any added items such as exhaust pipes.

Leaks in wooden roofs are commonly caused by a gap between the panels which move during expansion and contraction. This will help the new coating seal where it overlays the old roof coating edges and will reduce the chances of leaks at those locations. Some roofers also suggest using 6d roofing nails to secure the blister flaps.