The 10 Most Common Causes of Roof Leaks

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Whether your home is big or small, the last thing anyone wants is a roof leak. Image Via: Prentiss ArchitectsLet’s face it: No one wants to have to go running for a drip bucket every time it rains. Not only is having to stay on top of the weather forecast annoying and impractical, but that one small drip symbolizes a larger roofing issue – and we all know that roofing issues mean an investment of time and money.

In an effort to save you that investment, we’ve compiled a list of The 10 Most Common Causes of Roof Leaks. We’ll tell you what they look like, why they happen, and how to fix them.

Whether your roof is two years old or twenty keep this list handy. You never know when it could mean the difference between doing a quick repair or a major remodel.

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1. Your Flashing Has Cracked

What Does It Look Like: Flashing are thin pieces of metal that are installed under shingles and on the joints of your roof in order to create a water-resistant barrier, which can be concealed or exposed. If exposed, they will look like long runs of sheet metal and, if concealed, they will have a rubberized coating overtop. Broken flashing will feature large cracks

Why It Happens: Roofers often use tar to seal the flashing together and that can corrode over time. In the event that your flashing is left exposed, elements like wind and rain could be the reason behind its crack.

How To Fix It: (Via The Family Handyman): Once you locate the source of the leak, pry up the nails used to secure the old flashing. Lift any shingles out of the way and remove the cracked segment. Gently put a new run of flashing in its place, fasten the new flashing in the same pattern as your old piece using roofing nails. Then, apply a coat of roofing sealant to the nail heads. Routinely check flashing around your chimney and vents to ensure that cracks aren’t letting in moisture.

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2. You Have Broken Shingles

What Does It Look Like: Look up! This one is easy to spot. Since shingles are the exterior layer of a roof, you should be able to identify missing shingles by seeing different-colored patches on your roof. Alternatively, you may find the shingles themselves littering your yard after a heavy storm.

Why It Happens: Again, weather. High winds and heavy rains.

How To Fix It: (Via This Old House): Slide a pry bar underneath the row of nails that connects the damage shingle to the one below it. Lift up until the nail pops and then press down on the shingle while you remove the nail. Repeat for the remaining nails. Pull out the damaged shingle, replace it with a new one, and secure it with four new nails.

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3. Your Valleys Aren’t Properly Sealed

What Does It Look Like: An area where two planes of roof come together. Since, these areas of the roof are usually sloped, if the valleys are not sealed together properly, rainwater can get inside as it runs down the roof. You can detect a problem by searching for wet spots that run along the seams of your roof.

Why It Happens: A variety of reasons – the sealing may not have been done properly in the first place, it may have cracked when being stepped on, or an excess of rain and ice may have caused it to erode over time.

How To Fix It: This is one of those things that needs to be done by a professional because of its complexity and we do not recommend attempting it on your own. However, your roofer will likely fix the problem by laying a new leak barrier along the valley and shingling overtop.

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4. Your Vent Booting Is Cracked

What Does It Look Like: Roof vents are those things that look like small pipes sticking out of the top of your roof. They’re used to expel excess moisture from the inside of the house. Leaks from this area will likely leave corresponding dark spots (and mustiness).

Why It Happens: Roof vents are often sealed by placing some flashing around the opening and slipping a tight, rubber boot over the area where the pipe peeks out of the roof. Over time, the flashing can break or the roof can decay.

How To Fix It: (Via: DIY Guy): Use a knife to remove the rubber around the vent. Use a pry bar to break the seal on any connecting shingles. Slide the new rubber boot under the shingles, over the vent, and bring it down onto the roof. Then, secure the new boot with roofing nails on either side and caulk under the shingles to seal them to the new flashing. Consider buying extra shingles to make replacing broken ones even easier.

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5. You Have Ice Dam Buildup

What Does It Look Like: An ice dam is a ridge of ice that forms at the edge of a roof and prevents melting snow (water) from draining off. The combined weight of the ice itself can damage the roof, as well as the water just sitting on the roof’s surface.

Why It Happens: The heat from your attic (and the rest of your house) is above freezing, which causes some of the snowfall to melt, despite the cold temperatures outside. The water will then run between the roof’s surface and the snow and will refreeze into ice once it hit’s the roof’s exterior edge.

How To Fix It: Invest in a roof rake, which looks like a sideways shovel with a long handle, and use it too reach up onto the roof and remove at least the lower four feet of snow from the roof edge. If you see an ice dam forming, consider treating it with an ice melt product, according to manufacturer’s directions. As winter gets closer, be prepared to find a way to clear the snow off your roof.

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6. Your Skylights Were Improperly Installed

What Does It Look Like: Leaks from this kind of problem should be super easy to spot. If you find yourself noticing wet spots or consistently needing to place drip buckets around the sides of your skylights, you’ve found the cause. However, leaks and wet spots near the top of the skylight may be a flashing issue instead.

Why It Happens: There are two main causes for this type of leak. Improperly measuring and fitting the skylights upon installation or decayed insulation along the skylights edges.

How To Fix It: Clear any debris off of the skylight and check for cracks in the window itself. Seal any cracks with a layer of clear silicone along its length, if necessary. If that is not the cause, check the surrounding flashing and replace as needed. While skylights look pretty, they can let in extra moisture when not properly sealed.

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7. Your Gutters Are Clogged

What Does It Look Like: You may be able to see the leaves sticking out of the gutter when you look up onto your roof. But, if not, you should notice the lack of water trickling out of a downspout during a rainstorm.

Why It Happens: Your gutters are meant to help water travel away from the roof. When a blockage forms and they get clogged, that travel stops. Rainwater will then pool in one area of the roof and have more of an opportunity to seep through cracks.

How To Fix It: Sorry, there’s no easy answer to this one. Get up on a ladder, and get in there with your hands. Many recommend placing a large tarp underneath the area where you are working. That way, you can drop any debris as you go and wrap it up for easy disposal later. Clean your gutters in the spring and fall for peak water flow.

8. You Have A Cracked Chimney

What Does It Look Like: Most often, you can look for signs of wear and tear along the mud cap, or mortared area around the top of the chimney. You should also look for any holes in the mortared joints where the chimney connects with the roof. Also, be on the lookout for loose flashing and shingles in the surrounding area.

Why It Happens: Mortar is essentially just a thick mixture of water, sand, and cement. It erodes easily in harsh weather conditions.

How To Fix It: In some cases, all you need to do is find the source of the leak and replace the missing mortar. However, since the materials used for chimney repairs are different than those for standard roofing fixes, it is recommended that you hire a professional handle the repairs. If you have a link by your fireplace, a crack in the chimney cap is a good bet.

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9. There’s Condensation In Your Attic

What Does It Look Like: A leak is most likely coming from your attic if the space shows signs of mold growth or mildew. A strong, musty odor  emanating from the attic is also a key that water has gotten inside.

Why It Happens: As the uppermost part of your home, the attic is trapped between indoor and outdoor temperatures. When those clash – think hot summers and cold winters – condensation will form and moisture will follow.

How To Fix It: First, treat any mold growth. Then, take the time to isolate your attic to prevent large fluctuations in temperature. Make sure that all of the roof vents are clear from the interior end and install a large ventilation fan, if needed. Pay special attention to the venting from your attic to prevent condensation from causing a leak.

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10. You’re Using It Too Much

What Does It Look Like: Unfortunately, there is no way to differentiate if this is the cause of the leak. However, all homeowners should be careful with how often they venture out on to their roofs.

Why It Happens: As you can see from the other causes in this post, a lot of roofing material is very fragile. You may accidentally step on a crucial element or crack an already precarious seal.

How To Fix It: Avoid walking on your roof whenever possible. Let that Frisbee go and buy a new one. Hire a professional roofer to do your fixes, since they are trained on how to avoid the most easily-damaged areas. Save yourself from walking on the roof by growing a green oasis.

Whether you have an old roof, new roof, or even a fancy green rooftop, wear and tear is unavoidable. There will be rainstorms, long winters, and heavy winds. But, roof leaks? They are a different story. With the right care regimen, every roof should have the ability to keep your family warm and dry for decades. As you work on home maintenance, refer to this list of the 10 most common causes of roof leaks. You’ll be glad you did when catching a leak early saves you time and money.

Have you ever had a leak in your roof? If so, what did you do to fix it? If not, do you have any home maintenance tips that you use to keep the roof in good shape? Share your stories with us in the comments.