[an error occurred while processing this directive]
How to find a leak on a shingle roof
Dear Ms. Builder: When it rains, I see a discolored spot on the bedroom ceiling. I can see where it is dripping in the attic. The shingle roof is 15 years old. Any ideas on how to find the leak and fix it? - Nancy P.
Dear Nancy: Trying to find the leaking spot is literally like trying to find a needle in a hay stack. It's simple to go up into the attic and find the drip during a storm. Unfortunately, the leak can be more than 10 feet from the location of the visible drip.
The leaky spot is often further up on the roof than the location of the drip unless you have roof trusses. With trusses, the maze of lumber makes it tough to find. Next time it leaks during a storm, play detective. Take a roll of paper towels, a flashlight and a tape measure up into the attic.
Tear off a paper towel and touch it to all the lumber near and above the leaky spot. Although you may not be able to see the water trickling down a truss member, you will see a damp spot on the paper.
Use this paper towel method to track the water leak to its highest point inside the attic. If you are lucky enough to pinpoint the leaky spot, measure its location from the side and top of the underside of the roof. You will use these measurements to locate the spot on top of the roof.
If you were not lucky enough to find the source, the following are the most common roof leak sources - slots between shingles, valleys (where two roof angles come together), any metal flashing, plumbing vent flashings (usually a rubber material) and chimneys.
Wearing gym shoes, you can easily walk on most shingle roofs. Even so, if you are like me and uncomfortable more than three feet above the ground, use a rock or mountain climbers type of harness and support rope. Never go up on a roof without a helper around to call for help if you need it.
Since your roof is 15 years old, there is a good chance that the leaky area is in the slots in the common three-tab shingles. These slots take abuse from the water flow. Also, the top portion of the slot is the only area where there is only one layer of material between the rain and your ceiling.
Check the condition of the metal flashing any place that the shingles contact a non-shingle surface. Look for corrosion or cracked solder joints. You cannot fix this yourself. Check the rubber vent flashing for cracks. You should probably buy a new one and replace it yourself.
The telltale sign of a possible leak is a lack of fine shingle granules. The purpose of these granules on shingles is to block and reflect the sun's damaging ultraviolet rays. Without this protection, the asphalt shingle material becomes brittle, cracks and begins to leak.
It is not difficult to fix a leak at several of the slots. Buy tin sheet metal at your home center store. Cut it into strips 3 inches wide by about 5 inches long. Wear work gloves. The edges are sharp.
Carefully slide a tin strip under the top shingle slot, covering the exposed leaking area. Do this in the early evening when the sun is not intense, but the shingles are still warm and pliable. Use a flat pry bar to help loosen the shingle to start the strip.
Don't just slop roofing cement over the leaky area like icing on a cake. It will breakdown quickly in the sun. Roofing cement is formulated to bond shingle and roofing materials together, not as a coating.
Tools and materials needed: flash light, tin snips, tape measure, pry bar, safety gear, tin, paper towels, vent flashing
Send your questions to Ms. Builder, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com/msbuilder.