Many homeowners are surprised to learn that there is more than one way to install an asphalt shingle roof. Experienced Houston roofing companies use many types of shingles, each with their own manufacturer specifications on the ideal method of installation. An improper installation technique can have serious and long lasting consequences on a roof's performance, longevity and durability. Understanding the differences between installation techniques can help property owners recognize the signs of problems on their own homes or if they are considering the purchase of a house that is for sale. Homeowners can identify many of these issues on their own, or a professional roofing inspection can be done as well.
Offset installation is the preferred way of installing nearly all types of asphalt shingles. Once the starter course of shingles is laid upon the roof's decking, subsequent rows will be shifted slightly to the right or left. Only after many rows of shingles have been installed, will a joint between the shingles line up with the joint in the first row. The manufacturer may specify a recommended offset or the roofers may determine it on their own.
Roofers from Houston Restoration Services of Houston would be happy to answer any questions you have about storm damage or commercial roofing.
This installation method is the most common and helps to reduce wear and tear, uplifting, curling and granule loss.
Racking is another way that crews may put asphalt shingles onto a roof. This method involves every other row of shingles lining up at the seams. The racking process is only sometimes listed as acceptable and in a couple of types of shingles, it is the preferred way for installation. However, the majority of shingle manufacturers will not warranty a roof that is put on a home in this manner.
Another improper installation method is overexposure of the shingles. This is a technique in which too much of the height of the shingles is exposed to the air. When the shingles are not sufficiently overlapped vertically, they have an increased risk of uplifting, curling, cracking or getting blown off the roof. Overexposure also hastens granule loss, which promotes moisture infiltration and leaking. An overexposed roof may fail prematurely.
Telegraphing is another problem related to asphalt shingle installation. If an older layer of shingles or improperly laid roofing felt is left on the roof and then a new layer of shingles is installed upon them, problems such as buckling, curling or cupping may develop in the fresh layer. Removal of the old problematic layer of shingles or underlayment would have prevented the problem from recurring.
