If you’re in the process of getting a new roof, you’re probably hearing a lot of things about impact-resistant roof materials or asphalt shingles versus polymer modified shingles, as well as the expected lifespans of your roof depending on what choices you make. However, another important aspect to consider is whether your shingles-to-be have a good algae rating.

What is Algae?

Algae is a very broad term for a large and diverse group of photosynthetic eukaryotic organisms; for our purposes today, it’s a plant that grows on your roof and thrives particularly in warm, humid environments. If you’ve ever seen pieces of blue-green, fuzzy-looking growth on your (or anyone else’s) roof, that’s likely what it is.

What Can Algae Do to My Roof?

If you think algae is harmless to your roof, think again. It may not be a big deal at first, but it can attract a myriad of issues that you and other Indianapolis homeowners won’t want to deal with.

Leave Unsightly Black Streaks on Your Shingles

While the appearance of algae on your roof might even look pleasant to you at first – like a fairytale cottage – the truth is, it will cause aesthetic damage in the long run. A bacteria called Gloeocapsa magma causes the algae to leave a black tone all over your roof’s shingles, taking away drastically from even the most beautiful home’s curb appeal. In fact, the presence of algae on a roof can even bring down a home’s value.

Increase Your Energy Bill

Roof algae is high maintenance like other plants around your home, but not exactly in the same way. Algae will absorb the sun’s heat and force it into your home, making your air-conditioning unit work harder than it needs to in order to keep your house at a comfortable temperature. It won’t do any favors for your energy bill.

Create Potential For Other Damaging Growths

If the algae on your roof develops a relationship with the right types of fungi, you could also be dealing with growths called lichen, which appear more branch or leaf-like and have a crustier texture. Lichen is more destructive and harder to remove from your roof than algae, so it’s best to nip the problem in the bud when it’s algae alone.

Another concern when you have roof algae is the eventual growth of moss. Unlike algae or lichen, moss has hairlike structures similar to roots called rhizoids, which are bad news for your shingles – they’ll actually find their way underneath the shingles and cause weak spots and holes, compromising the integrity of your entire roof system. Plus, moss is known for absorbing moisture, which could attract bacteria, mold and mildew to your home as well.

Algae-Resistant Shingles: Choose Prevention Over Treatment

Now that you understand what algae (and other things that can come from it) can do to your roof, we can get to the main point: What is an algae rating?
Depending on the types of shingles you’re considering for your roof, some will come with a certain level of algae resistance, indicated by an algae rating – the higher the rating, the more likely it is that the shingles will withstand the discoloration that comes after years of algae growth. These types of shingles look just like regular ones, but they’re made with copper granules, stopping algae in its tracks much more effectively. The manufacturer should indicate how many years the algae resistance will last; once that timeframe passes, you may notice some algae growth, which you can remove by doing a soft wash.

Soft washes break apart the algae and lichen on your roof using a lightly sprayed chemical. Be sure to hire a roof cleaning and maintenance contractor to do it for you, because it’s important to get the chemical mixture right. If you hire someone who isn’t experienced or licensed, or you try to do it yourself, you’ll risk leaving your roof discolored, which is exactly what you’re trying to avoid by doing the soft wash in the first place! Always consider quality over price and choose a licensed, bonded contractor to do any repair or installation work on your roof or home.

What NOT to Do About Algae on Your Roof

If your anxiety is mounting over the algae on your roof, the temptation is probably pretty high to blast it all away with a power wash. However, you should not do this under any circumstances! Sure, it might get rid of the algae, but it’ll also leave your roof more vulnerable because it would wash away the protective granules from your shingles. These granules are critical, and washing them away would mean wasting a huge part of your investment in your new roof; they help reflect light from the shingles and reduce heat absorption (think about your energy bill!), plus they protect the shingles from the elements and add weight to strengthen them.

Another reason power washing is a bad idea is your roof simply isn’t made to handle the amount of pressure you’d be putting on it, especially for an extended period of time. It could result in shingles coming off of your roof or sealants being damaged, which increases your risk for one or more leaks. Worse yet, there’s a chance power washing will spread the algae around to areas it didn’t take up residence before, which certainly defeats the purpose of your efforts. As tempting as it is to do, a soft wash is by far your best option and is safest for the integrity of your roof.

Roof Experts in Indianapolis

Questions on selecting shingles with the best algae rating, or need to get rid of algae that are already present? At Indy Roof & Restoration, we believe in offering outstanding service, whether you simply have a question or you need a comprehensive roof inspection and repairs. Call us today to let us know how we can help, and we’ll walk you through every step of our process.

Aaron Christy

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