Removing Mildew From Asphalt Roofs

You could use regular household bleach to remove the algae from your roof.

Removing mildew from asphalt roofs.

Spray wash the roof with a 50 mix of water and bleach to get rid of the algae. Roof shingles are exposed to a lot of wear and tear as extreme heat sun wind and precipitation come into contact with them. Though often attributed to an accumulation of dirt defective shingles mold or mildew. If you live in a humid area of the country you ve probably seen unsightly dark streaks on asphalt shingle roofs.

Commonly found in climates with warm humid summers it does no damage to the roofing but it certainly does looks bad. Do it yourself and save big bucks. Moss build up can lead to roof damage or shingle blow off if left unchecked. Removing algae stains from roof shingles is easy with the right technique.

Extensive mold growth can also expose the interior of your attic or crawlspace to mold spores carrying the problem over to the inside not to worry though because you can clean the mold off with basic household bleach and save. Mold stains can form on roof shingles that are in permanent shade. Keeping branches trimmed back from the roof and removing any debris that begins to accumulate should be part of a regular roof maintenance program. If moss or algae becomes visible clean the roof.

Using shingles that have been treated with algicide keeps the growth at bay for about 10 years thus the 10 year algae warranty. They re likely to damage the shingles. One way to determine if it s mildew is to put a few drops of chlorine bleach on to the black mark. If it s dirt the dark stain will remain but if it s mildew the stain will go away.

So it pays to clean your shingles as soon as you spot algae growth. But once the algicide wears off your roof hosts an all you can eat buffet for the neighborhood algae spores. The most common culprit is actually a blue green algae known as gloeocapsa magma that is spread by airborne spores. Algae and moss growth on roofs at a minimum is an unsightly nuisance.

These stains will discolor your roof and damage the shingles over a period of time if left alone. The black mold like stains and streaks that appear on roofs particularly light colored asphalt shingles is actually a blue green algae gloeocapsa magma. No pressure washers please. To remove the algae from asphalt shingles you have a few options.

A few years ago commercial roof cleaning products containing hydrogen peroxide lye were commonly recommended to remove mildew. It is not uncommon for roof shingles to turn black over time.