Decay of roof shingles, sheathing, and/or siding
Possible cause: Poor attic ventilation

Missing, cracked or curled shingles
Possible cause: Shingles have reached the end of their useful life

Dark, "dirty-looking" areas on your roof
Possible cause: Environmental pollutants; vegetation, fungus or algae;

loss of granules due to age of shingles

Excessive energy costs
Possible cause: Insufficient attic ventilation causes heating/cooling system to run excessively

In warm weather, inadequate ventilation will trap hot air in the attic, causing air c onditioning systems to work harder,

This condensed moisture can drip down onto the insulation and reduce its effectiveness.
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