Few things in life are more frustrating than waking up to the slow and monotonous dripping of water between a ceiling and floor. In such cases, there is clearly some sort of roof damage, but identifying the source of a roof leak often requires a great deal of deductive reasoning powers. Before you call in the contractor or roof specialist, however, it would be a good idea to check your roof flashing. This is often where most leaks begin, and if such is the case, the repair is relatively simple. New pieces can often be screwed or glued in place, although the seals may need to be removed and new caulk or roofing cement installed first.
In many cases, you will not need to replace the roof flashing at all. A few simple repairs, requiring little time, may well stop the leak in short order. Granted, the process can sometimes be one of trial and error, but more times than not, you will be able to solve the problem on your own.
The flashing is located at intersection points on your roof, in spots such as peaks and valleys where water is likely to collect and pool. It can be made of galvanized steel, copper, aluminum, or even vinyl. You will find it under the shingles running along the peak of a roof, but also around chimneys, vent pipes, and skylights. Really, flashing is normally installed at any point on the roof where there is a dramatic change of angle. When well installed, it will prevent the leaks from these areas, but age, time, or the hazards of weather can damage it.
Your first step is to locate the flashing, lifting a few shingles if need be to see if the nails holding it in place have pulled away and left a water-welcoming gap. If such is the case, the material can re-anchored, but pounding in new nails is not the best fix. A better choice is to screw the flashing down, matching the screws to the same material from which the flashing is constructed. Cover the screws with a waterproof substance, such as a silicon seal.
Roof flashing sometimes develops holes, often from hailstorms. If you find a hole, simply cut a patch from an extra piece of flashing and thoroughly clean and smooth the area around the hole. Make the patch slightly bigger than the hole on all sides, and then glue it down with roofing cement. After this has dried, it is a good idea to apply another coat of cement on top of the patch. There really is no such thing as overkill when attempting to fix a roof leak.
Flashing around chimneys and vents is another story. If these pieces have pulled away, it is because the seals that hold them in place have either rotted or been broken. Chip away the old seals, again thoroughly clean and remove any excess debris, and apply either caulk or roofing cement as needed. Reinstall the flashing into the correct position, and hold or clamp it in place until the seal has dried.
If none of these options work, and you still are placing pots and pans on the kitchen floor to collect dripping water, the problem may not be the flashing. In this case, it is very likely that you have worn out or damaged shingles. Your options, in this case, will be to seal the entire roof with a synthetic coating, apply roof tar or cement to suspected leak spots, or replace the entire roof.