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With winter on the way, many homeowners are thinking flashlights, snow shovels, and bags of ice melt. But when storms hit, you may have no better friend than a can of roof cement.

roof cement, leaky roofUse disposable tools and wear vinyl gloves when working with roof cement. It has a way of getting everywhere. Photo: Joe Provey, Home & Garden Editorial Services

Your roof is your house's first line of defense against the elements. It quietly does its job day after day. Many of us don't give it a second thought -- until there's a problem.

So stay one step ahead of trouble. In these last days and weeks of relatively comfortable weather, it's the perfect time to inspect your roof for leak-causing damage (especially after a storm). Look for shingles that are askew or missing. Check for exposed nails. If you can safely climb up on the roof for a closer inspection, check every joint for splits, cracks and openings. Joints include the "seams", called valleys, where one roof plane meets another. They also include around penetrations, such as dormers, chimneys, skylights, vent, and waste stacks.

roof cement, leaky roofPhoto: Joe Provey, Home & Garden Editorial Services

A can of roof cement will fix most roofing problems. For example, if you spot a popped nail (a common entry point for water) working its way through the surface of a shingle, hammer it back in place.

roof cement, leaky roofPhoto: Joe Provey, Home & Garden Editorial Services

Then spread a dab of roof cement over the exposed nail head to prevent water leakage. You may "camouflage" the patch by scraping the granules from a spare shingle and spreading them over the roof cement.

roof cement, leaky roofPhoto: Joe Provey, Home & Garden Editorial Services

You may also use cement to mend a torn shingle, "glue" down a loose shingle, or attach a new one. In all three cases, apply cement generously underneath the shingle, then press it back into place.

Flashing is another common leak point. Made of rectangular pieces or long strips of thin metal, flashing is a critical component of any roof, but it may crack with age. Look for flashing along valleys and around the perimeter of penetrations. If you spot a crack, use roof cement to seal it. It will keep water out until it's time to re-roof, at which point you should replace the flashing. Apply a 1/4-inch-thick and 3- or 4-inch-wide layer of cement over narrow cracks and tears. If the break is 1/4-inch wide or larger or several inches long, apply a thin bed of cement and embed an open mesh glass fabric in it. Then cover with additional cement.

roof cement, leaky roofChoose a roof cement, like this type by Karnak, that can be used in both wet and dry conditions. Photo: The Home Depot

There are several types of roof cement sold at home centers. To be on the safe side, opt for one that indicates it can be used in wet, cold conditions. Roof cement is available in 10 oz. cartridges, gallon cans, and 3.5 gallon cans. While the cartridges are a bit easier to work with, my recommendation is to pick up a gallon. You'll be surprised at how much you'll need to make a patch. Roof cement has a way of making a big mess, so also pick up plenty of disposable vinyl gloves and several disposable plastic trowels in varying sizes.

In order to have your roof cement ready to go, store it at room temperature. Otherwise, you will have to keep it at roof temperature for 24 hours until you can use it. Clean surfaces of dirt, gravel, and debris; and scrape away old roof cement to obtain a smooth patch. When applying to metal, remove rust and oxidation with a wire brush.

21 Tips for Readying Your Home for Winter (WalletPop)
All About Roof Shingles (ShelterPop)
Perform a Basic Roof Inspection (Lifehacker)

  • Sue

    Some of these tips Http:// helped us save a lot of water damage from our roof this fall.

  • JohnTheBuilder

    Roofing cement can be a good way to TEMPORARILY repair a roof but once it's applied, you'll have to check it very often. Freeze/thaw cycles make it shrink and expand wildly which will result in cracks that will need to be refilled. I've been roofing on new and remodeled homes for 40 years and as I always say "If it's new, it shouldn't have ANY, and if it's a repair, it's gunna need a new roof SOON!"

  • george t

    can you use roofing cement as a temp fix if it is kept in the cellar warm the weather out side is 30 degrees ?

  • 3 Comments / 1 Pages

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