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Roof Leak: Signs to watch out for

Home inspectors do not begin examining a roof with a flashlight in the attic, but rather on the ground outside the house with a pair of binoculars. These are not lazy or fearless people (if the latter is true, then they made a very bad career choice); they're looking for obvious signs of trouble, like missing shingles or holes made by animals, as well as standard red flags, like skylights and plumbing vents. They then check the attic for any signs of water and double-check all the trouble spots noted during the ground inspection.

If you see water damage on your ceiling, don't assume it's caused by a hole in the roof directly above. It could get in just about anywhere and wind its way down the underside of the roof deck before it falls onto the back of the ceiling, thanks to gravity and liquid adhesion (yes, there's a name for that). You can sleuth your own leaks by starting outside, then going to the attic with a flashlight.

Here are 7 obvious trouble areas to look at:

1. Plumbing Penetrations: Building contractors know that running a pipe through a roof is akin to drilling a hole in a boat and plugging it with rubber, but it must be done. There are many penetrations in an attic, including plumbing vent pipes, exhaust flues for appliances, attic vents, and ventilation ducts. Among the most common leak sources are worn or cracked rubber boots and metal flashing around pipes and flues.

2. Flashing: Flashing is any thin metal sheet, strip, angle, or fitting that covers a seam or transition in a roof. Flashing has proven to be the best band-aid for transitions on roofing materials. Flashing leaks tend to start where it is damaged, corroded, or completely missing (how much did your last roof cost?). Additionally, flashing should be present and intact at all dormers, valleys where two different roof planes meet, and where a roof meets a wall.

3. Skylight: A roof window or skylight is an excellent way to add light to a home. Even if you enjoy a little rain on occasion, you'll eventually receive that as well. The presence of water anywhere near the downhill side of a skylight indicates the unit (or more likely, its installation) is performing its less-publicized function: leaking.

4. Chimney: You're a smart guy, or at least you're getting a sense of what roofers deal with when it comes to chimneys. If you think it might be tough to seal every millimeter of airspace between a brick wall and a plywood floor. A chimney stack not only creates a huge hole in a roof but also collects water on its surface, which can trickle down and get into the smallest cracks. Flashing failure is the most common cause of chimney leaks. Also, if your chimney isn't at the peak of your roof, it should have a cricket -- a triangular metal tent on the high side where the stack meets the roof. A chimney without this feature can lead to water pooling at the base, and pooling water can significantly damage the roof.

5. Shingle Damage: The shingles themselves might be the last thing to cause a leak unless you have been walking around on your roof in golf spikes, but they don't last forever. Old shingles can simply wear out enough to fail, but more common problems include cracked, cupped, damaged, or missing shingles. During a storm, the shingles along the peak and ridges are most susceptible to wind damage. Nails driven through shingles and not sealed (with roofing cement) also tend to leak. Nails make holes. When installing a metal roof, make sure you keep an eye out for corrosion, especially where dissimilar metals come into contact, such as where an aluminum vent cap is installed on a steel roof. When it comes to tile and slate roofs, broken and missing shingles and failed repairs are cause for concern -- both for your roof and your wallet.

6. Ice Dams: Each year, viewers in cold climates look forward to local TV news coverage of ice dams... It's like waiting for the next flu virus. For those of you who missed the most recent news flash, ice dams are caused by melting snow on a roof, then running down toward a cold eave and freezing. Ice eventually backs up under the shingles, where it melts and drips into your house. It is indeed a vicious cycle. The solution? Insulation and air sealing above the home's living space, and better ventilation in the attic, to keep it cold (while lowering your heating bill).

7. Meteorites: This is not usually the case. But have you heard about Radivoke Lajic? Whose house in northern Bosnia has reportedly been struck six times by meteorites since 2007, may consider this cause for a roof leak to be common. Even lottery players don't have to worry about a meteorite causing a roof leak in their home if they are not Mr. Lajic.

How to Trace a Leak

Water leaks usually appear as dark streaks on the underside of the roof decking, the plywood, or the board layer under the shingles. Follow these streaks up the roof to where they appear to originate. You might not be there yet. Water can travel along the top of the roofing felt (tar paper) before it penetrates the sheathing, and even then it needs to find a crack or seam somewhere before it can reach the underside. Following the water markings will help you find the leak source, hopefully saving you from using an entire case of roofing cement (now available in convenient tubes!) trying to stop the leak.

Roofing professionals can help you find and repair roof leaks. Contact APD Roofing and we’ll help you find a solution to your leak problem.

"VERY professional, and timely. Communication with clients and with the insurance company is exceptional! Workers are respectful, pleasant, and knowledgeable about the scope of work assigned. Could have not chosen a better company to work with when I experienced roof issues and needed a roof replacement. Thank God for APD..."

Morgan Pressley | Houston Texas


Lead Claims Consultant, IICRC Certified

Chief Operations Manager

APD Roofing

April Cumbalon

Marketing Assistant/Office Manager

APD Roofing


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