Skip to main content

«  View All Posts

Roof Replacement

Does Moss on Your Roof Mean It Needs to be Replaced?

June 9th, 2023 | 5 min. read

Does Moss on Your Roof Mean It Needs to be Replaced?

Print/Save as PDF

Moss forms when moisture mixes with debris left to sit on your roof. While it may take time to form, the longer it sits on your roof, the more it shortens your shingles’ lifespan. 

But most homeowners don’t notice moss until it’s taken over a good-sized area. This leaves them wondering if the moss growing on their roof means it’s time for a replacement. 

For over 30 years, the team at Bill Ragan Roofing has taken pride in answering all the roofing-related questions homeowners have. That’s why I’ll help you understand what moss means to your roof and what to do about it. 

By the end of this article, you’ll have the answer to these questions:

  • Does moss on your roof mean that it’s time for a roof replacement?
  • Can moss be cleaned off your roof?
  • Should you try to clean moss off your roof by yourself?

Does moss on your roof mean it’s time for a roof replacement?

While moss on your roof is a sign that it’s time for a new roof, it doesn’t necessarily mean your roof needs to be replaced as soon as you notice it growing. It could be growing from debris built up, lack of sun hitting a damp roof, overhanging trees, etc. 

moss growing on an old asphalt shingle roof

However, moss and other vegetation growing is usually a clear sign you have an older roof. So, while it may not need replacing right away, it’s time to start thinking about a new roof.

moss growing on asphalt shingle roof

You may think you can get by with removing it from your older roof, but moss sitting on your roof damages the asphalt shingles. There’s no telling the damage waiting underneath when it’s removed.

At the end of the day, moss on your roof doesn’t mean you need a new roof right away, especially if your roof isn’t near the end of its lifespan and the affected area is small. However, an older roof with moss means you need to start budgeting for a new roof before leaks show up. 

Can moss be cleaned off your roof?

Yes, moss can be cleaned off of your roof. There are a few different ways to do this yourself or what a professional roof cleaner will do. 

You can use a low-pressure hose to wet the moss and remove it by hand, but this is extremely time-consuming and dangerous. The next way is to bleach the moss.

According to the Asphalt Roofing Manufacturers Association

“The most effective method of cleaning algae and moss from a roof is with a 50:50 mix of laundry strength liquid chlorine bleach and water. Apply with a sprayer and allow the solution to dwell on the roof surface for 15 to 20 minutes, and then rinse thoroughly with low pressure water.”

Before doing this, just know that bleach can discolor your shingles just like it does clothing. So, there’s a decent chance you’ll have some spottiness. The last way is to use a moss control powder on your roof, but the effectiveness varies. 

Now, your first instinct to get rid of moss is to use a pressure washer. It makes sense for most external house cleaning, but it damages asphalt shingles and blows their protective granules off. 

Should you try to clean moss off your roof by yourself? 

After learning how to clean moss off your roof, you’re probably ready to start the process. But is clearing moss off your roof something you should do yourself or hire a professional? 

We are a roofing company, so we recommend hiring a professional. However, I recommend hiring a roof cleaning company specializing in moss and other vegetation removal instead of a regular roofing company.

While I’ll always recommend a pro, your roof is your property. So, it’s completely up to you to determine if it’s worth cleaning moss off your roof. 

However, you need to think about your safety by considering if you can walk on a roof, how you handle heights, and your comfort level on a ladder. If you aren’t absolutely 100% confident that you can clean your roof safely, don’t even attempt it. 

You also have to accept that you could end up damaging your roof more, leading to costly problems. Depending on what you do, you could even void your warranties.

For safety reasons and to ensure it’s done correctly, it’s a good idea to contact a professional. 

What are the other signs that it’s time for a new roof?

Now you know if moss on your roof means you need a new roof, if it can be cleaned off your roof, and if you should try to do it yourself. Remember that moss on your roof doesn’t necessarily mean you need a new roof. 

You won’t know until you contact a professional roofing company to determine the next steps and whether a replacement is warranted. However, moss on your roof is a good indicator that your older roof is starting to show signs of needing a replacement. 

Just know that there are other ways your roof tells you it’s time for a replacement. Ignoring these signals leads to costly problems and causes damage to the interior of your home.  

I don’t want this to happen to you. That’s why I wrote another article that helps you spot the right time to replace your roof. 

Check out 5 Warning Signs You Need a New Roof to learn when you should start considering a roof replacement.

New call-to-action

Table Of Contents

Related Articles