Mold Or Rot -Mold is the most dangerous to the roof. Mold is the main cause of roof leakage. Rots cause huge damage to the roof. Broken Or Torn Shingles - Replacing broken shingles is very important. Due to broken shingle roof leakage occurs and make serious damage to interiors. Aging - In the ideal condition, the life span of the shingle is about 20 to 30 years. Proper Mentaince required for shingle roofs. Sign Of Water Damage -Water damage is an obvious indication that your roof needs to be inspected by a roofing expert. Visit our blog to know more about when to replace shingles.