Top 10 reasons that your roof might need to be replaced
If There has been a major HAIL STORM or WIND STORM in your area.
If there is a considerable amount of shingles missing on several slopes of the roof.
If your roof system is older than 20 years you might want to consider a new roof system rather than repairing your existing system.
Your roof leaks in multiple areas.
The shingles on your roof are excessively curled or buckled, or a number of tiles are cracked or missing.
The roof is stained or covered with mossy growth.
Stains are appearing on interior walls, ceilings and attic rafters.
Sagging decking between the rafters. If the decking is sagging or deteriorating, the decking will also require replacement when a new roof is installed.
Outside light that can be seen through the roof. This may be common (and not a problem) but it is best to have a professional make this determination.
Signs of water damage or leaking (usually in the form of water stains, or sagging ceilings)—this could be due to an active leak in the roof or to condensation caused by poor roof ventilation.
