Asphalt shingles are one of the most popular roofing materials because they last a relatively long time and cost less than other materials like wood and slate shingles. However, they're still prone to certain types of damage and discoloration. Many manufacturers have begun adding copper particles to the granule covering on the shingles. Learning why these copper particles are often included may convince you to upgrade to a roofing product featuring them.
Black Algae Growth
Unlike moss, black algae is a type of plant growth that doesn't hurt the shingles themselves. However, it's still an unwanted addition to a roof because it creates large and spreading streaks of black or grey discoloration as the algae breaks down and releases staining chemicals. It often takes multiple rounds of bleaching the roof with an oxygen based bleach product to remove the stains, so it's far easier to just prevent the algae from growing in the first place. Asphalt shingles are particularly prone to black algae growth because they're manufactured with limestone mixed in as an additive to strengthen the fiberglass material, and the limestone acts as a easily digestible food supply for the algae.
Alternative to Flashing Strips
Roof shingle manufacturers offer asphalt products with copper particles included so you don't have to install lengthy and costly copper flashing strips at the peak of each roof line. Copper is the best deterrent to black algae growth because it continually sheds molecules of the metal when exposed to water and sunlight. These invisible bits of metal prevent the algae from growing and have no effect on the roofing materials or the ground around your home. Flashing strips have to be applied on the top of the shingles to work in this way, and many people don't like the look of visible copper flashing. Copper particle shingles are a good alternative, but must be used over the entire roof.
There's no need to settle for a different style of asphalt shingles just to get the protection offered by copper particles. The metal particles are easily colored without interfering with the efficacy of the treatment, allowing you to enjoy a roof of any color or style with the same protective benefits. No one will know your roof has copper protection unless you tell them, so be sure to mention it if you're selling your home because long-term protection against black algae discoloration is a distinctive selling point.
Contact a company, like Pyramid Roofing Inc, for more help.