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How to Remove Mold from your Roof

When roof mold forms, it often leaves dark black streaks that discolor the shingles and nearby siding and diminish exterior aesthetics. Far from being merely an eyesore, roof mold can also affect the health of building inhabits. This is especially true for anyone with asthma, allergies, or other chronic respiratory conditions. Spores from roof mold can travel into the house via the air duct or A/C system. If left unchecked, this mold can even be washed down onto your driveway, walkways, and other frequently traveled areas where it will eventually be tracked inside.

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Roof mold can be problematic in many other ways. Given its darker color, this mold has a tendency to attract and retain sunlight. Thus, when it becomes widespread, it can make your home hotter in the summer months, drive your energy bills up, and lead to a marked increase in your household’s carbon footprint. It can also be odorous, and it’s known to gradually erode roofing structures and surfaces, thereby leading to the need for expensive repairs. Known as Gloeocapsa magma, roof mold is an invasive algae with a distinctive blue-green color. It’s most common in hot, moist climates, but your home can also get it if you live in any perpetually damp region. The good news is that getting rid of roof mold is often easy.

The Best Way to Get Rid of Roof Mold

One of the most effective and commonly used strategies for eliminating roof mold is to apply a solution of one part bleach and one part water to all affected surfaces. This will kill the mold and remove the discoloration so that the home is safer, protected against further damages, and more aesthetically pleasing. You may have heard that roof mold is most common on light-colored shingles. In reality, however, if the environmental conditions are right, this mold can grow on shingles of all colors. It’s just easier to see on lighter shingles. Moreover, even if your home’s shingles are dark and mold isn’t readily apparent from the sidewalk, this doesn’t mean that it’s not causing property damages and that you’re not at risk of having it enter your home and wreak havoc on resident health.

There are several things to remember when using bleach and water to fix this problem. To start, you should never attempt to apply this solution with a pressure washer. Most pressure washers that homeowners can purchase in-store have a single, high-power setting. This equipment is designed to use extreme force to power off dirt, grime, and other elements. In fact, it so forceful that it can damage shingles or lift them off. If pressure washing is necessary for eliminating your mold problem, hire a professional roofer to do the job. Roofing companies have access to commercial-grade pressure washing equipment that comes with soft-wash settings. These settings are perfect for eliminating blue-green algae from rooftops without causing structural harm. 

When applying bleach on your own, start by wetting the foundation plantings. This will keep them protected from the bleach so that discoloration doesn’t occur. Before getting started, you should also:

  • Put on a pair of safety goggles to protect your eyes
  • Wear a mask to avoid bleach fumes and exposure to mold spores
  • Put on a raincoat or other waterproof gear to avoid exposing your skin to bleach

Place your bleach and water mixture into a spray bottle and then use this to liberally wet the entire affected area. Let the solution sit for about 15 minutes before thoroughly hosing the treated space down with a standard garden hose. You should also rinse all surrounding areas. Although chlorine bleach is the most effective bleach for both killing roof mold and eradicating the black-looking streaks that it causes, using it too frequently can cause your roof’s shingles to weaken. 

If your roof is nearing the end of its lifespan and is due for a replacement, you should consider having shingles with copper granules installed. This is all the more true if you’ve had a long-running battle with roof mold in the past. Due to copper’s natural antimicrobial properties, roofing elements that contain copper can effectively stave mold formation off. If you need assistance in cleaning your mold-covered roof or want to know more about roofing materials that are designed to prevent mold, we can help. Call us now at 913-850-6556.