Algae on Roof: What Is Roof Algae and How Do I Fix It?

Out of all the things that you need to worry about on your roof, you probably haven’t considered roof algae to be a problem. Depending on the extent of the algae and how much it has spread, you’ll likely need to take steps to get rid of it. 

The good news is that it’s fairly simple to remove, and the sooner you can do it, the better. Here’s how to recognize it, and what to do once you’ve ascertained that roof algae is the problem. 

What Is Roof Algae?

Firstly, you need to be able to recognize roof algae and get the help you need for it. Typically, algae will look like discoloration of the roof. There can also be black or brown streaks or spots that look like mold. In many cases, homeowners will assume that the marks are mold when really they’re algae. 

It is important to understand that algae and mold are two different organisms. Algae aren’t as harmful to humans as mold is, but it can cause damage to your roof too. It can also spread rapidly, so it’s best to address it as soon as you can. 

The best way to ascertain if it’s algae on your roof is to look at the color. It will typically have a black–green color, while mold will be black or brown. It will also grow in blotches, rather than in streaks like algae. 

The Causes Of Roof Algae

Why is algae growing on your roof? There could be several different reasons why you’re starting to see it. As a plant, it thrives on both moisture and heat, making your roof the best place for it in certain conditions. 

If you have a lot of shade over your roof, then that’s going to help algae grow faster. The actual materials on your roof will give it nutrients, too. Asphalt shingles typically have limestone filler, and that’s something that algae can thrive on. 

All you need is one algae spore making its way onto your roof, and then it can start to grow. If you have wet weather, it will help it grow faster. Humid weather will also help spread algae, too. 

Why You Need To Remove Roof Algae

So now you can recognize what roof algae looks like, you need to know just why it needs to be removed. There are several reasons why you should clean it off, as soon as you see it starting to form:

  • Improve the appearance of your roof: If nothing else, the growth of algae on your roof will affect how it looks. It can make your home look less well cared for, even when you’re taking good care of it. It also affects the curb appeal of your home too, something you’ll need to consider even if you’re not looking to sell any time soon. 
  • Roofing material damage: The longer that algae is allowed to stay on your roof, the more damage it will do. It will adhere to the materials, and cause staining. It will also damage the underlying materials, and after long enough will cause the materials to need to be replaced. 
  • Rot: One of the problems with algae is that it traps moisture against your roof. Over time, that moisture will make it’s way into the roofing structure, and that encourages wood rot and mold to form.
  • Damage to other structures on your property: If algae is allowed to grow on your roof, then you’ll soon find that it starts sending spores into the atmosphere around it. That allows algae to start growing on other structures nearby, causing more problems for you. 
  • Health issues: While algae aren’t as harmful to health as mold or mildew, it can create the best conditions for them to form. That creates health hazards in your own home, that can be avoided. 

Cleaning Roof Algae

With all this in mind, it’s always best to clean off roof algae as soon as you’re aware of it. When you see you have algae, you’ll find there are lots of ways of treating the issue yourself. While some cleaning solutions will give you good results, it’s hard to know just as a homeowner which is the best for you. Also, there’s the issue of safety while working on your roof. 

As such, it’s always best to call a professional to take a look at your roof and give you a quote for cleaning it. The cost of this cleaning is always going to be cheaper than having to pay for roof repair or replacement, later down the line. 

Like most things in home repair, prevention is always better than cure. You’ll be able to take steps to stop algae from forming on your roof in the first place. Firstly, look at the trees near your roof. If they overhang, they’ll be giving shade to the roof, as well as causing other issues such as dropping leaves into your gutters. You can trim those branches back, or remove the tree altogether. 

On the subject of blocked gutters, ensure that you’re cleaning your out regularly. That will help water run away from the roof as it should, as well as prevent other issues, such as ice dams

When you’re having your roof replaced, you can look into algae-resistant materials. This is something you should do especially if you live in a humid region. 

When Algae Leads to Roof Repair

If you need algae cleaned off your roof, it’s always best to call a professional. Not only can they do it safely, but they’ll be able to tell if the roofing materials have been damaged. If they have been damaged enough, it may be prudent to replace the roof to ensure your home has adequate protection. 

As you can see, it’s always best to handle algae as soon as you see it on your roof. Call a trusted roofer to come and handle the cleaning for you, and you’ll be able to keep that roof in top condition.