Repair Flat Shingled Roof

Tips on Repairing a Flat Roof with Cracked, Pealing, Bubbling or Split Shingles

By Mark J. Donovan

You basically have three courses of action to repair a flat shingled roof when it springs a leak. First, if the shingled flat roof is relatively new you can try contacting the roofing contractor who installed it to come and repair it. Second, if the shingled flat roof is older and you can’t either find the original contractor or he refuses to repair it, you can do your own flat roof repair. Third, if the flat roof is quite old, you can find a new flat roof installation contractor to replace the original flat roof.

Regardless of what path you precede down to repair a flat shingled roof, it is best to quickly pull out the buckets to catch the water dripping in the home.

Once the weather has abated and the roof is reasonably dry place a tarp over the roof until you can actually perform the roof repair.

How to Repair Flat Shingled Roof

After the weather has improved the first step in repairing a flat roof is finding the leaking area of the roof. Once you have located the damaged shingles, remove any dirt and dust from the area. It is critical that the leak area be completely clean to enable the roofing cement to stick to the surface of the roof.

Use a utility knife to cut out the cracked or peeling section of shingles on the flat roof. Try to make neat and regular shaped cuts such as a square or rectangular shape. A carpenter’s square works great for making straight cuts. This way you can use the cut out pieces as templates for fabricating the new sections of flat roofing shingle material, however make sure to cut the new sections of roof shingle material approximately 2 inches wider than the sections you cut out. Note that you may end up cutting through a couple of layers of shingles to get to the roof sheathing. If this is the case you will need to cut enough patches to bring the repaired patch up to the finished level of the adjacent roofing shingles. Flat shingle roof repair using roofing cement.

Next, apply roofing cement under the edges of the area that you cut out. Use a putty knife to help lift the shingle edges while you apply the roofing cement.

Then apply roofing cement in the cutout area. Use the putty knife to spread the roofing cement out evenly.

Press the new bottom layer shingle piece(s) into the cutout area and tack it down with roofing nails.

Then apply the top larger layer shingle(s) over the bottom one(s). With the top layer shingle(s) you can simply nail them down and forgo the cement with them.

If there are any exposed nails when complete, which there should not be if the top layer shingles are nailed down correctly, apply roofing cement over the exposed nails.

Finally, apply roofing cement around the perimeter of the top patch to form a tight and permanent seal.

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Split or Bubbling Flat Shingle Roof Repair

If during your inspection of the flat roof you identify a split or bubbling shingle, simply cut the shingle along the split or bubbling line with your utility knife and apply roofing cement underneath the shingle edges on each side of the cut. Then apply a couple of roofing nails to each side of the cut and apply a shingle patch over it as described above.

For more help on Shingling Your Home’s Roof, see’s Asphalt Shingle Roofing Bid Sheet. The Asphalt Shingle Roofing Bid Sheet will help to ensure that your roof won’t end up with a blue tarp over it and a dumpster sitting in your yard for weeks as you wait for the roofing contractor to come back and finish roofing your home.

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