The most obvious sign of a leaky roof is water falling into your house. But you can detect a leak before it becomes that obvious. If you have brown, discolored spots on the drywall ceiling, there is water leaking in. And even if there are no visible signs of a leak, water leakage can rot the roof framing system, compromising its structural integrity, requiring increasing and costly repairs.
Prevention with inspection
For this reason, it is best to try and prevent leaks with regular roof inspections – twice a year, as recommended by the National Roofing Contractors Association (NRCA). It is best to do inspections once in the fall and once in the late spring, as the winter is the toughest season for a roof. Many roofing contractors will provide a free roof inspection, including a written estimate indicating the required repairs, as a means to solicit work.
In the event of a leak, take immediate action, as a leaky roof can cause significant damage to insulation, walls, ceilings, flooring and personal property. Larger leaks will unduly cause greater damage, but even a tiny leak can cause enough damage to require replacing the entire ceiling.
Check the flashing first
The most common cause of roof leakage is not faulty asphalt shingle, but the flashing around the chimney, vents, fans and skylights, and lining roof valleys and eaves. Often, the asphalt compound or caulking material used with flashing – or the rubber used for sealing pipes and other protrusions – dries out from exposure to the elements and the sun's UV rays. The dried out materials crack or loosen the seal, allowing water to penetrate.
The good news is that these types of problems can usually be fixed quite cheaply with asphalt cement – a repair that will last around three years. Alternately, you can replace the flashing, which should last more than ten years. Rusted and corroded flashing can also be the source of leaks. They can be cleaned up and painted with a rust-resistant paint to squeeze more years of service, but severely deteriorated flash and vents should be replaced.
Replace old, worn out shingles
Another reason for a leaky roof is old age. When asphalt shingles begin to curl, crack or tear, or when the mineral granules wear off revealing the black asphalt, they need to be replaced. If only a few shingles are affected, a repair job will do. But if the wear is noticeable in one out of every five to ten shingles, you may need to replace the roof.
Blowing tree limbs and debris can cause small cuts and tears in asphalt shingles, leading to roof leaks. It is fairly easy to repair or replace single shingles and a handyman or roofing contractor can do the job. Trim tree branches at least 8 inches from the house to prevent damage to the roof.
Clear away leaves and debris
A buildup of leaves and debris in the roof valley can cause water backups to leak through the roof. Keep an eye out for debris on the roof and clear it away as soon as possible. Debris that has been sitting on the roof for awhile may have caused some rotting of the wood frame and sheathing, and may require a roof inspection. Also, gutters filled with leaves and debris, and clogged downspouts, allow water to back up, which can cause leaks in the roof. Gutters should be cleaned out periodically, and downspouts checked for clogging.
A buildup of ice at the eave, often called an ice dam, can also lead to roof leakage. It can even cause structural damage to the roof's framing system. One of the best ways to prevent an ice dam is by using an eave-heating system – heated wires that are strung on the roof above the overhang which prevent the water from freezing, and promoting proper watershed. A worthwhile investment if your roof is given to ice dams.
Call a professional for a roof inspection
With all the sources that can cause a leak in your roof, it is a good idea to hire a roofing contractor to inspect your roof. For smaller repairs like shingle replacement or re-applying caulking, you may be able to save some money by hiring an experienced handyman. But for bigger repair jobs to your asphalt shingle roof, it is best to call a professional roofing contractor.