See the large black or dark streaks coursing down your roof? Those aren’t weather-related stains – that’s algae and mold slowly growing and putting your roof’s health at risk. One of your roof’s biggest enemies is the organic matter that grows on your roof, and finds your roof a perfect breeding and feeding ground. The health of your roof is greatly compromised by common molds and algae that populate on your roof – and it may be there without you even knowing.
Algae on your roof primarily feeds on the limestone filler commonly found in asphalt shingles. The limestone gives weight to the shingle, but it also provides a nice food source for the algae, particularly blue-green algae. The algae eats away at the limestone, and erodes your shingle’s ability to provide the necessary protection for which it’s designed. While limestone is the primary food source, moisture and other environmental conditions provide it the nutrients it needs to flourish. If your home is in an area where the relative humidity tends to be higher, this should also cause you to pay close attention to the organic growth potentially on your roof.
Preventing common mold and algae on your roof can save you a ton of trouble (and money) down the line. Here are five tips to keep your roof algae-free.
- Keep Your Roof Surface Clean
- This may sound like a simple one, but it’s probably the most effective. As leaves and debris commonly accumulate on your roof, they hold moisture and create a breeding ground for mold and algae. Use a leaf blower to simply remove any of these uninvited guests. We’d recommend avoiding the use of a pressure washer – it’s dangerous and may actually void your roof’s warranty protection.
- Trim Overhanging Branches
- Sunlight and circulation are your roof’s best weapons against any organic growth. Trim back tree branches to allow Mother Nature’s sunlight and air to reach your roof. Avoid letting anything sit on your roof — like tarps or branches — for long periods of time. If your roof stays damp and shaded, that’s prime breeding ground for mold and algae.
- Improve the Drainage Around Your Roof
- Proper water drainage from your roof will not only help keep it free from algae growth, but (bonus benefit!) it will also help keep your foundation at the foot of your home solid. Due to the weight of clogged, overflowing gutters, they degrade the roof’s structural integrity. When that water pours down around your foundation, basement leaks now become a concern. Make sure the gutters are clean and downspouts clear so water drains away properly.
- Apply Algae-Resistant Treatments
- Most home improvement stores sell zinc or copper strips that you can place along the roof ridge, which can become an easy way to allow the rainwater to carry the metal down the roof to kill algae and mold. If you’re putting a new roof on your home or you’re building a new home, look for algae-resistant shingles — they’re designed to keep organic growth at bay through their composition.
5. Ventilate the Attic
- Your attic can rise to pretty opressive temperatures if not ventilated correctly. That hot, stale air sitting in your attic provides an unfortunate foundation right under your roof to encourage mold and algae growth. Ensuring your attic is well ventilated will help keep your roof consistently dry.
Bonus Tip:
With any of these tips above, your safety is always priority #1! Never put yourself in a situation that compromises your safety – and always have someone with you if you ever work on or near your roof. There’s no amount of maintenance that’s worth you being injured trying DIY projects on your roof.
If you’d like help in identifying any potential issues with your roof, call the experts at Roof Scientist today for a free, no-obligation plan to keep your roof free of mold and algae.
