A shingle roof is a system, where each sheet contributes to the stability of the one above and below it. Get it right, and you have a composite structure able to withstand violent storms. Get it wrong, and you could have a roof waiting for its moment to start leaking.
Most Calgary home owners are at a disadvantage because they don’t understand the right way to fit shingles. Moreover, they are unlikely to climb up on the roof and check the work in progress. Cowboy roofers know this, including the out-of-towners who left a mess after the last big storm.
You Need Someone Who Knows the Right Way to Fit Shingles
Most installers know the right way to overlap shingles to create the desired pattern. They have to, because that’s what the average home owner tries to check from the ground below. However, it’s harder to determine whether the three lower nails on each shingle are driven in correctly from a distance.
They are supposed to be within the lower ‘nailing strip’ where they go solidly through the upper ‘nailing strip’ of the one below. That way, each shingle has six nails holding it in position. However this needs accuracy, because the nailing strip is only a half to one inch wide.
Get this right, and you have your overlapping system where each shingle contributes to the stability of the one above and below it. Get it wrong, and you have weak points the fingers of a gale can reach under and lift.
You Need Someone Who Knows the Right Way to Fit Nails
No roof is 100% flat and even. Asphalt shingles are semi-soft and pliable, so they can follow the gentle waves. Therefore, you have to drive in the nails correctly so the heads press gently down of the surface. Here’s what we check for during roof inspections:
1… Are the nails driven sufficiently far in? If some heads are protruding, that allows space for those tiles to lift in strong wind and admit moisture.
2… Are some nails driven too far in below the surface of the shingle? If so, they could cause them to curl, or crack over time and admit moisture flowing down the roof.
3… Are some nails driven in at an angle? These can leave a gap rainwater can penetrate and cause damp and rot over time.
These could count among your problems if you have a leaky shingle roof. We offer a roof inspection service to clients in Calgary. Give us a call at (403)829-1661 if we can assist.
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Image: Asphalt Shingle Texture: Shadowmeld Photography BY CC 4.0