Roofing is one job that most of us are happy to leave to a professional. Still, there are a few important maintenance and repair procedures that can keep a roof from leaking in extreme weather conditions.
It's often the occasional leak that starts a roof sliding toward total replacement.When a roof leaks after 4 inches of rain but not after 2 inches of rain, or perhaps only under heavy snow cover, chances are that the leak is not in the larger field of shingles.
More often, an occasional leak will occur around plumbing or heating pipe flashings, above a skylight or near valley tin. Luckily, most of these conditions can be corrected with a few low-dollar maintenance and repair steps. Even roofs that do not leak deserve a yearly inspection.
Often a leak is evident, but its source is not.
The reason is that roofs are built in layers, often with a layer or more of roofing felt (tar paper) beneath the shingles. In other cases, the visible layer of shingles
covers previous layers.
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As a result, water can move laterally, or even up the slope a little (by means of capillary action), before dripping into the attic. This makes pinpointing a leak, or predicting the source of future leaks, a little tricky.
Simply knowing about the problem helps. If there is no apparent problem with the field of shingles, look to the valleys of flashings, even if they are 3 or 4 feet away from the leak.
Flue or plumbing stack flashings, as well as roof vent flashings and valley tin can be treated with a little roofing compound. Fiber-impregnated roofing compound is a tar-like substance that stays in place even in hot weather.