prevent shingle roof discoloration

Discoloration on your shingles can detract from the appearance of your home, but even worse, the underlying cause may damage your roofing material and shorten its lifespan. There are various types of discoloration that can appear on a shingle roof, so it’s important to know what to watch for so you can keep your home looking good and avert costly damage.

Here’s a brief primer on three kinds of discoloration that often affect Atlanta roofing materials.

Reddish Stains

Many items found on a typical shingle roof are made of metal such as flashing, a chimney flue, mounting for an antenna, exhaust vent covers and skylight trim. With time and exposure to the elements, these metal materials can start to corrode. If the deterioration isn’t noticed and addressed, you’ll see ugly red-colored staining running down your shingles from the corroded item.

Green Patches

If the north side of your roof is shaded most of the time, you may start to see patches of green moss develop, especially in areas where moist debris tends to accumulate. Moss can loosen the edges of your shingles so they’re more vulnerable to storm damage, and pull water underneath where it can cause leaks and decking/structural damage.

Black Streaks

Algae that causes roof discoloration in hot, humid climates is a fungus that’s spread via airborne spores. Although the brownish-black streaks caused by algae growth make your roof look unsightly, the fungus doesn’t usually cause any damage if it’s cleaned off promptly using a safe and effective method.

Tips to Prevent Discoloration on Your Shingle Roof


  • Have your roof inspected once a year. A knowledgeable roofer can spot any newly developing issues so you can get them fixed before discoloration occurs. This is especially important to prevent rust stains, which are almost impossible to remove without ruining the shingles.


  • Get your roof professionally cleaned periodically. Your roofer has the right tools, know-how and solutions to safely and effectively remove staining caused by algae or moss growth.


  • Eliminate debris build up. Debris like dead leaves, seed pods, pine needles and twigs creates the ideal growth environment for algae and moss. In addition to having accumulated debris cleared away often, get the limbs of surrounding trees trimmed back at least 10 feet from your roof to minimize any build up.


For more advice about preventing shingle discoloration on your roof, contact the Atlanta roofing experts at Pro Roofing & Siding.

Read: Make Sure Your Roof Holds Up to the Weather