How Much Does a Bucket of Roof Cement Cover?

Application

• Roof cement comes in buckets weighing from 1 to 5 lbs. and the coverage area depends upon the use. When used as a straight patch for a large area, the manufacturers of PERMAROOF Patching Cement recommend an application rate of 40 to 50 linear feet per gallon for a 1/4-inch thick layer. If the roof cement is used with two layers with fabric between them, then it will cover 20 to 25 linear feet.

Other Uses

• Roof cement can also be used to spot patch and to bind shingles together. For example, a nail can pop, or rise above, an asphalt shingle. This is easy to hammer back in but it almost always leaves a small channel where water can leak through to the plywood. Coating the underside and shank of the nail with cement on a small brush before forcing it back in, and then covering the top and 1 inch around it will prevent leaks.

Loose Shingles

• Wind can lift shingles off from a roof and loosen them with little outward damage. Walking the roof and lifting the edge of the shingles randomly will reveal a problem. If four or five shingles in a contiguous area lift easily then you should brush a thin layer of room cement under them to bond them again to the lower shingles. Test the shingles in about 48 hours to ensure the bond is holding. Otherwise, the loose shingles are vulnerable to the next heavy wind.

Transition Leaks

• Roof transitions are highly susceptible to leaking. When a roof meets a skylight, a vent flue or a chimney, the flashing around the area needs to be done properly or else a problem will develop. If you suspect that one of these areas are weak, a layer of roof cement extending a foot around the area might help. A thin coat in a leaky metal gutter will also prevent water from dripping through.