- Caused by leaks in roof. Check attic or crawlspace for leaks in deck
- Check chimney and vents for cracks in flashing
- Check rafters for leaks that travel away from original source
- Check roof for damaged shingles
- Caused by improper installation (on new roof)
- Caused by drying and cracking (on old roof)
- Can sometimes be repaired without replacing roof
- Caused by improper fastening
- Caused by exposure to high winds
- Can usually be replaced individually
- Caused by improperly applied felt (buckling)
- Caused by movement in deck (buckling)
- Caused by under saturation of felt in organic-based shingles (curling)
- Caused by application over wet deck
- Caused by moisture in shingle
- Caused by inadequate ventilation
- Caused by growth of airborne algae deposited on roof
- Unsightly appearance does not affect the service life of the material
- Common problem in warm, humid climates
- Algae resistant shingles available regionally
- On newly applied shingles, a certain number of loose granules is normal
- On aging shingles, missing granules indicate need for replacement