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Addressing the issue of moss and algae growth on a current asphalt shingle roof can be done with several practical solutions for immediate results. For longer-lasting prevention, Malarkey introduces shingles equipped with advanced 3M™ Copper Granules, providing a resilient barrier against algae infestation.

The development of moss and algae on asphalt shingles can be a widespread issue for homeowners, particularly in wet and humid regions. If neglected, these organic intruders can cause significant harm to your roof, resulting in leaks and expensive repairs. Expert roofing contractors should inspect your roof for damage and remove moss and algae on a regular basis to keep your roof in good condition and extend its lifespan.


Moss and Algae: Understanding the Difference?

Often misidentified as mold or mildew, the black spots and streaks observed on numerous roofs in the United States and Canada are typically algae. These tend to form where moisture accumulates on roof surfaces. Coastal or humid environments are prime locations for algae proliferation, according to the Asphalt Roofing Manufacturers Association (ARMA). Algae discoloration usually begins as small spots that rapidly turn into streaks on the roof surface. When you can see the algae, it has probably been there for months or even longer.

Moss, in contrast, is a plant that gathers water through its foliage, not its root system, and thrives in damp conditions. In areas like the rain-soaked Pacific Northwest, where Malarkey’s headquarters in Portland, Oregon is located, moss is a usual occurrence. It’s commonly found on the north-facing slopes that receive less direct sunlight and remain damp for more extended periods. Overhanging branches add extra shade and drop debris on the roof, which retains moisture and acts as a nutrient source for moss, as per ARMA. Unlike algae, moss can cause the leading edges of shingles to lift or curl, increasing the risk of shingle detachment during windy conditions.

Prevention: A Proactive Approach

Prevention is always better than cure. The optimal method to address moss and algae on your roof is to avert their growth altogether. Regular roof maintenance, including cleaning gutters, trimming overhanging trees, and removing debris such as leaves and branches, is a good starting point. Roofing professionals often use a broom or leaf blower to clear the roof. These practices prevent moisture accumulation and decrease the probability of moss and algae development.

Without algae protection, roofs in coastal and damp climates can display black streaks on shingles in as few as three years. To counter this, several Malarkey roofing shingle lines feature Algae Resistance (AR) using 3M™ Copper Granules. These granules blend seamlessly into a shingle’s color and distribute evenly on the shingle’s surface, releasing copper ions that inhibit algae growth, stopping it before it begins. For optimum algae protection, Malarkey shingles with Scotchgard™ Protector use at least a 10% blend of 3M™ Copper Granules, granting Malarkey the honor of being the first shingle manufacturer in the U.S. to receive the Scotchgard™ Protector label from 3M.


Why Not Just Clean the Roof?

In the roofing industry, safety is paramount. If you’re a homeowner who isn’t comfortable, trained, or properly equipped to safely work at elevation, it’s advised to hire a professional roofing contractor. Attempting to remove algae-induced black streaks via pressure washing can be extremely slippery and hazardous. Moreover, pressure washing can remove a shingle’s granules, which are its primary defense against damage and UV aging.

What Are the Maintenance Choices for Moss and Algae on Old Asphalt Roofs?

If you’re not prepared to install new algae-resistant shingles, there are several strategies (each with its own advantages and disadvantages) to limit moss and algae accumulation.

  • Chemical treatment: This approach applies a specific cleaning solution to affected roof areas, designed to eliminate moss and algae and prevent regrowth. While ARMA suggests a 50:50 mix of laundry-strength liquid chlorine bleach and water as the most effective method, this can have detrimental effects on local environments and watersheds. An eco-friendlier alternative includes natural compounds like white vinegar, which is cheaper and less harmful to the ecosystem.
  • Manual removal: This involves physically removing moss and algae with a scraper or brush, which can be labor-intensive but effective for smaller infestations. Remember, excessive foot traffic on shingles can also remove granules, accelerating their aging process.
  • Installation of zinc or copper strips: These can prevent moss and algae growth by releasing metal ions that inhibit their development, similar to 3M™ Copper Granules.

With a bit of effort and some readily available household items, you can remove moss and algae from your asphalt shingles and preserve your roof. If you live in a place that is always wet and muggy, it’s worth noting that some shingles are designed for algae resistance, helping to prevent algae accumulation. Always prioritize safety when working on a roof, and in most cases, it’s highly recommended to hire a professional roofing contractor.

Secure Your Roof with AJT Roofing and Contracting:

The Professionals in Algae and Moss Removal

Don’t let moss and algae take over your roof! Here at AJT Roofing and Contracting, we know how to protect and preserve your roofing system using the most effective and safe techniques. Living in a damp climate? Consider our algae-resistant shingles for long-lasting protection against algae accumulation.

Your safety is paramount to us. That’s why we always recommend hiring a professional when dealing with roofing projects. You can trust our team of skilled contractors to deliver excellent service that prioritizes your home and safety.

Don’t delay! Contact AJT Roofing and Contracting today, and let us take care of your roofing needs. Your home deserves the best, and we’re here to provide it.

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