- Shingle edges are curled or shingle tabs are cupped.
Asphalt roofing shingles with curled edges
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- Bald spots where granules are missing
- Cracked shingles.
Cracked asphalt roofing shingles
- Your roof is at least 20 years old; while many shingles today are produced for durability, many factors can accelerate the aging of shingles. For example, if your roof is not properly ventilated, it can negatively impact your shingles.
- The roof just looks old and worn.
Visible signs of aging on a 3-tab asphalt shingle roof
- Neighbors are getting new roofs. Homes built around the same time period can be experiencing the same types of weather conditions can mean that your roof is nearing its useful life.
- Dark streaks. Airborne algae cause dark streaks on roof decks. While this may not necessarily harm the roof shingles, it may not look good. Algae streaks can be removed using a 50:50 blend of water and bleach sprayed on your roof. It is important to use a low volume garden hose so you do not knock the protective granules off your shingles. It is also important that you protect your landscaping from the bleach run-off.
3-tab asphalt roofing shingles with algae/dark stains
- Moss can grow on roof surfaces that don’t get much sunlight, especially in cool, moist climates. Moss growth can be more than a cosmetic issue. Moss holds moisture against the roof surface and overtime in freezing climates can cause damage to the granules on the top of the shingles. Moss can be brushed off but it won’t prevent it from growing again; take care not to damage the shingle surface. You may need to contact a professional roofing contractor.
Moss growing on asphalt roofing shingles
Asphalt roofing shingles with missing granules
Some images, as noted, were provided by Haag Engineering.