My home is a 17 year split level in the Washington, DC area. We still have the original roof and 1 layer of shingles (also original). I don't know how to tell when the shingles need to be replaced. Other homes in the area are having the shingles torn off and replaced, but we get alot more shade than most

We have no leaks and no drainage problems from the roof.

The black shingles are beginning to curl at the lower corner edges in some areas, less than 1/8th inch.

Any advice is appreciated.
Thanks

 

At 17 years old, you have approached the life of the shingles. The curling you mentioned also is a sure sign that the roof is beginning to fail. Also, look for a buildup of roofing granules in the gutters and around the downspouts.

I would begin to budget for a new roof in the not too distance future.

Many roofers will install a roofover on a house that has only one layer of shingles but I always recommend that the old shingles be stripped. The roofover is less costly and no disposal of the old roofing material is needed but next time, you have to tear off and dispose of 2 layers of shingles.

 

If your shingles are 17 years old, they have already out lived their live by 2 years. 17 years ago they had a 15 year life span. time is up. Strip off the old roof, and make sure you use 30 lb felt. If you roof over, in a couple of years, your roof will look wavey.