Repair & Maintenance · FAQ

Are algae-resistant shingles worth the upgrade?

Yes if your home is shaded or north-facing — that combo is where streaking shows up worst. Algae-resistant shingles use copper-impregnated granules that release small amounts of copper ion as rain hits them, which kills the bacteria before colonies form. GAF StainGuard Plus, CertainTeed Streak Fighter, and Owens Corning Streak Guard all use this technology.

The cost premium is small ($5 to $12 per square) and the warranty against streaking typically runs 10 to 25 years. Trill installs algae-resistant shingles on roughly 70% of Madison County roofs because tree cover is widespread in our service area. The exception is a fully sun-exposed roof with no tree cover where streaking won’t be a problem anyway. Worth asking your installer which shingles include the resistance and which don’t.