Decay of roof shingles, sheathing, and/or siding

Possible cause: Poor attic ventilation.

Leakage in attic after wind-driven rain

Possible cause: Leaky or inadequate shingle
underlayment or deteriorated flashing

Stains on interior ceilings and walls or mold and mildew growth

Possible cause: Inadequate or faulty shingle underlayment allowing leakage or inadequate ventilation.

Dark, "dirty-looking" areas on your roof

Possible cause: Environmental pollutants; vegetation, fungus or algae; loss of granules due to age of shingles.

Missing, cracked or curled shingles

Possible cause: Shingles have reached the
end of their useful life.

Excessive energy costs

Possible cause: Insufficient attic ventilation causes heating/cooling system to run excessively.