Is there a coating you can put on shingles?

Yes, there are coatings you can put on shingles, but most shingle manufacturers do not recommend them and some coatings can void warranties, so caution is needed. There are several types of coatings marketed. Elastomeric reflective coatings, often white or light colored, are designed to reflect sunlight and reduce cooling costs on flat or low-slope roofs, but they are not recommended for steep-slope asphalt shingles as they can trap moisture and prevent shingles from shedding water properly. Asphalt shingle rejuvenator coatings claim to restore oils to aged shingles, typically using soybean oil or other bio-based emulsions, and may temporarily make shingles look darker and more flexible, but independent testing shows limited long-term lifespan extension. Algae-resistant coatings containing zinc or copper are available and can help prevent biological growth. Clear sealers are sometimes marketed as waterproofing, but asphalt shingles are already waterproof and adding a sealer can interfere with factory sealant strips and granule adhesion. If you are considering a coating, understand that GAF, Owens Corning, and other major manufacturers state that applying aftermarket coatings may void their limited warranties. The best way to extend shingle life is proper ventilation, regular cleaning with shingle-safe cleaners, prompt repair of damaged shingles, and keeping gutters clean, rather than relying on coatings. If you want reflective benefits, consider cool roof rated shingles at replacement time.