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How to Tell if a Roof Stain Is Old or New

Roof stains often occur in warm, humid areas like Marietta. Roof stains pose an even bigger problem for homes with light-colored roofs. Though the issue is largely a cosmetic one, roof stains can have a significant impact on home value and homeowner pride. Knowing whether a roof stain is new or old will be a big help if you are trying to fix the problem or are shopping for a home for the first time.

Understanding Roof Staining

The staining you see on Marietta roofs usually comes from a form of algae called gloeocapsa magna. According to the Asphalt Roofing Manufacturers Association (ARMA), this algae causes discoloration in any type or color of roofing.

This type of staining does not happen overnight. Algae is collected little by little until it becomes visible from the curb or upon closer inspection. Because of the gradual growth of the algae, roofers may find it difficult to determine whether the staining is an old or new phenomenon. The best information can be gathered following a cleaning. When roofers look at areas where staining was detected, they sometimes find the shadow of spots. These areas represent the oldest discolorations on a roof. The longer the spots linger, the harder they are to remove.

Stain Removal Options

Because algae staining gets worse with time, a homeowner's best defense is regular roof inspections and cleanings. There are several techniques used to treat stained areas. If high-pressure spraying is not appropriate due to the type of roofing material used, a roofer may turn to gentler spot cleaning.

When removing roof stains, professionals will take your priorities into account. If appearance is of paramount importance and the roofing has a short life expectancy ahead— the suggested solution may be different than the resolution recommended for a brand-new roof that's stained.

Moss Stains

Algae spots are not the only type of stain found on a roof. Moss stains from overhanging trees cause similar discoloration. Moss stain removal requires cleanings. Metal flashing is a tool roofers sometimes add to a structure in order to limit the recurrence of staining.

If your roof has reached the end of its useful life and you are replacing it, algae-resistant shingles are an excellent choice to consider. If you're having roof stain problems in Marietta, contact the professionals! They'll treat unsightly stains on your roof and can recommend a treatment that will get your roof looking its best.

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Findlay Roofing 4181 Jvl Industrial Park Dr, Marietta, GA 30066 e-mail: sales@roofroof.com