Moist weather conditions promote the growth of algae and mold on roofs. You typically can see the problem easily because dark streaks and patches will discolor your roof. You must not ignore these telltale signs of roof mold. The microorganisms will slowly damage your shingles and eventually let water penetrate farther into your home’s structure. On top of this, the mold poses health risks to occupants of your home.

Why Does Mold Grow on Roofs?

The blue-green algae called Gloeocapsa magma, commonly known as roof mold, takes hold on roofs in moist weather conditions. As you can imagine, wetter climates are the most prone to this type of growth.

The mold spores normally take hold on sections of a roof that face to the north. The northward exposure limits sunlight. This is why one side of your roof may look good while the other side has unsightly dark streaks.

If you see the dark mold spreading on areas of your roof facing other directions, it is probably because of shade cast by large trees. The lack of sunlight allows the roof to stay wet, especially in humid weather. This moist, low-light environment promotes the mold, and the problem will not get better without intervention.

Relationship Between Asphalt Shingles and Mold

Asphalt shingles are most at risk of developing a mold problem because their highly textured surfaces provide bumps and crevices where airborne mold spores can thrive. Additionally, filler materials used in the manufacturer of asphalt shingles contribute to mold growth.

Crushed limestone in particular is a shingle ingredient that helps mold grow. If sunlight is lacking, then lingering moisture combined with limestone filler literally provides algae with a food source.

How Mold Damages Your Roof

Because the mold consumes substances in the shingles for food, the shingles gradually become compromised. They will become thin in places or crack.

Shingles are the first line of defense in a roof. If they cannot repel water completely, then water gets under them. Water penetration, even in minor amounts, shortens the life of a roof.

Mold growth often covers a relatively large area of the roof. For this reason, once the shingles deteriorate, you can expect multiple sheets of roof decking or other structural elements to suffer water damage.

A full-blown leak may develop that you see come through your ceiling or in the walls. Even before that happens, rot may have claimed the wooden elements of the roof.

At a certain point, roof replacement becomes necessary. In Marlborough and Needham, Loyalty Exterior Solutions solves roof problems like these for homeowners. Our skilled team performs both roof repairs and roof replacements.

If we catch your roof mold problem early enough, we might correct the situation with roof cleaning that strips away the mold. We may recommend that you get tree trimming done if shade from branches is causing the problem.

When damage has progressed, we will determine if a repair will be enough to protect your home or if you need a new roof. We install either shingles or metal roofs. You may want to explore the benefits of metal roofing if your home is liable to suffer new mold growth due to its northern exposure.

Health Risks of Roof Mold

The threat of structural damage gives you plenty of motivation to fix your roof mold problem, but roof mold can have health consequences too. The microorganism growing up there spreads by airborne spores. These spores can enter your home.

Roof mold spores may infiltrate your home by entering roof vents or drifting in open windows. You may even track them into your home after walking on the sidewalk covered with spores washed down by a recent rain.

If you or a family member suffers from allergies, then breathing mold spores could worsen the condition. Spores may also aggravate respiratory problems like asthma.

Complete Roof, Siding and Deck Services

Maintaining or updating your home’s exterior is a big job that you can entrust to Loyalty Exterior Solutions. Our experienced professionals work hard to preserve the integrity and beauty of our clients’ homes. Our roofing services go beyond shingles and metal sheets. We install gutters and solar panels too. If you want to revitalize your home’s appearance, talk to us about deck repairs or installing new vinyl, wood, or fiber cement siding. Reach out to us today with your home exterior questions.

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Laryssa G
Laryssa G

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