Environmental Roof Enemies
Many factors affect the life-span of your roof. Knowing about your environment and the following will help you make informed roof system buying decisions:
- Sun: Heat and ultraviolet rays cause roofing materials to deteriorate (faster on the sides facing west or south.)
- Rain: When water gets underneath shingles, shakes or other roofing materials, it can work its way to the roof deck and cause the roof structure to rot.
- Wind: High winds can lift shingles’ edges (or other roofing materials) and force water and debris underneath them.
- Condensation: Condensation can result from the buildup of relatively warm, moisture-laden air. Moisture in a poorly ventilated attic promotes decay of wood sheathing and rafters, possibly destroying a roof structure.
- Trees and leaves: Falling branches from overhanging trees can damage, or even puncture, shingles and other roofing materials. Leaves on a roof system’s surface retain moisture, cause rot and block gutter drainage.
- Shingle deterioration: When shingles are old and worn out, they curl, split and lose their waterproofing effectiveness. Weakened shingles can be easily blown off by wind gusts, resulting in structural rot and interior damage. A deteriorated roof system only gets worse with time and should be replaced as soon as possible.
- Moss and algae: Moss can grow on moist wood shingles and shakes, causing rot. In addition, moss roots also can work their way into a wood deck and structure. Algae grows in damp, shaded areas on wood and asphalt shingle roof systems, causing rot and deterioration. Algae also grows on clay and concrete tile roofs near the ocean. Trees and bushes should be trimmed away from homes and buildings to eliminate damp, shaded areas, and gutters should be kept clean to ensure good drainage.
- Missing or torn shingles: The key to a roof system’s effectiveness is complete protection. When shingles are missing or torn off, a roof structure and home or building interior are vulnerable to water damage and rot. Nearby shingles can be easily ripped or blown away, quickly spreading the problem. Missing or torn shingles should be replaced as soon as possible.
- Flashing deterioration: Many apparent roof leaks really are flashing leaks. Good, tight flashings around chimneys, vents, skylights and wall/roof junctions can prevent water from entering a home or building and cause damage to walls, ceilings, insulation and electrical systems. Flashings should be checked as part of a biannual roof inspection and gutter cleaning.
- Snow and ice: Melting snow often refreezes at a roof’s overhang where the surface is cooler, forming an ice dam. This blocks proper drainage into the gutter. Water backs up under the shingles (or other roofing materials) and seeps into the interior.
How Do You Know When Your Roof is in Trouble?
- Shingles that are warped, blistered, missing or torn
- Shingles covered in moss or algae, which hold moisture and encourage rot
- Cracked tiles
- Gapping shakes
- Warped, split or thinning wood shakes
- Loose material or wear around chimneys, pipes and other penetrations
- Sagging roof line
- Overhanging tree branches that could gouge the roof in a strong wind
- Excessive debris (leaves, dirt, ice, roofing granules) in the gutters or downspouts, which block drainage
- Dark, dirty-looking areas – signs of fungus or mold
- Loss of granules on composite shingles
- Dark water stains in rafters or insulation
- Light passing through pinholes in wooden roofs (attic)
- Ceiling spots or leaks
- Cracked paint
- Stains on interior walls
- Discolored plasterboard
- Peeling wallpaper
- Higher than normal energy costs
- Mold, mildew or rot in the walls, ceilings, insulation and electrical systems