Roofing shingles can be made from many materials, including wood, metal or thin pieces of overlapping slate. But far and away the most popular material in the US is asphalt shingles. The reason is they’re easier to apply, they’re relatively inexpensive and, when installed correctly, they can last decades depending on the slope of the roof.
Many weather issues can cause shingles to come off of your roof. It’s hard to speculate what might cause this to happen. Once the underside of the shingles is exposed to the wind, the lifting and tearing force can easily defeat the roofing nails that hold the shingle in place.
Modern shingles come with self-sealing asphalt cement designed to interlock the bottom of each shingle with the one below it. If the missing shingles are on a steep north-facing side of your roof, it is possible this sealing compound never got to activate as well as it should have.
When the sun’s rays hit shingles, it heats them up, causing the self-sealing compound to activate. In most situations, this compound does a magnificent job of welding the shingles together.
The roofing nails that hold in the missing shingle or shingles in place may not hold well for a host of reasons. Maybe the nails were not long enough. If you can gain access to the attic space below the roof where the shingles are missing, inspect the roof sheathing to see if it’s rotten, has cracks or is soft.
If you have shingles that have blown off your roof, ask at least two independent roof inspectors to come out and give you an opinion. If you tell them you just want them to look at the roof, you could get a significant discount on the fee.
If you it is decided that your existing roof is in good shape and you can have the missing shingles replaced or you can choose a whole new roof. For more information on roofing materials and roof inspections, contact SB Roofing.