How to Fix a Leaking Tar Roof
- 1). Locate the source of the leak. Many leaks can flow under the roof before entering the house, so "it's above the living room" isn't accurate enough. Beginning at the lowest point of the roof where water is most likely to pool, sweep and shovel away loose gravel until you find blisters, cracks or other openings in the tar.
- 2). Cut the roof surface with a utility knife to expose the bad portion. In the case of blisters and other holes, cut a large X over the damage. For cracks, cut a perpendicular line across the crack every few inches.
- 3). Peel the cut flaps back and allow the inner surface to dry completely. If necessary use rags to clean out any water, mud and other debris from the area.
- 4). Apply a thick layer of tar under the cut area with a trowel. Once this is done, press the flaps back in place.
- 5). Spread a layer of tar over the cut area, extending it several inches past the area. Feather the edges into the existing roof.
- 6). Cut a piece of fiberglass cloth large enough to fit over the repair area.
- 7). Place the fiberglass onto the tar and press it in place with the trowel, allowing it to saturate until tar begins to seep through the glass mesh.
- 8). Apply a final thin coat of tar over the fiberglass to seal it in.
- 9). Replace the gravel over the patch by hand: sweeping it in place may disturb the patch. The gravel protects the tar from sunlight.
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