
Todd Kennedy
Owner of K & D Roofing
When you’re wondering how to clean roof shingles, you may think a quick blast from a power washer is the solution. However, that common approach can seriously damage your shingles and void your warranty. Before you make a costly mistake, you need to know the right way to remove those unsightly black streaks and green moss.
While it’s always easier to call in the roofing pros for cleaning, it’s definitely not the cheaper option. That’s why we’re giving you the best DIY ways to tackle this task. We’ll show you the correct methods for how to clean roof shingles, ensuring a safe and effective result. Whether it’s as simple as spraying down the roof or giving it a good scrub, you should feel confident to complete this job after reading this article and mastering how to clean roof shingles in 2025.
Your roof is one of the most important parts of your home. Not only does it keep you and your family dry, but it also helps protect your house from the elements and severe weather. That’s why it’s so important to know how to clean roof shingles, keeping them in good condition – not just for aesthetic reasons, but for practical ones too!
One of the big reasons you’re going to want to keep your roof clean is to extend its life. The cleaner the roof is, the longer it will last and provide better protection for your home.
If you’re wondering whether or not your roof needs to be cleaned, then it likely does. The roof might have stains, streaks, or other abnormal colors that give you an indicator of how clean it is.
Two main types of algae grow commonly on roofs throughout the United States. If you notice either type of algae on your roof, then make plans to clean right away.
Less common than the Gloeocapsa Magma algae, Fire Moss is still commonly found on roofs throughout North America. Cedar Shakes and Asphalt Shingles are the two most common roofing materials that it will grow on. The Fire Moss loves to latch on to the roof and reproduce.
Over time the moss can get out of hand and push up the shingles, allowing water to get underneath and behind, causing problems.
This algae leaves big long black streaks on shingles. Most commonly found on asphalt shingles, this spore-based algae is attracted to the limestone commonly used in shingles.
If this algae is left untreated, it will feed and degrade the limestone and eventually take over the entire roof, causing a multitude of problems.
When you are wondering how to clean roof shingles, this decision must be taken: softwashing vs pressure washing. If you want to keep your roof clean without damaging it, it’s essential that you know the difference between soft washing and pressure washing. Soft washing specifically refers to cleaning the roofing with less than 1,000 psi or pounds per square inch, while pressure washing uses greater than 1,000psi.
Only some materials will be able to handle the force of pressure washing. This makes soft washing a much more common option because you’ll get close to the same effect without damaging the roof system.
Here are the materials that are commonly safe to pressure wash:
Most other materials can be damaged in some way if you pressure wash them.
The below materials are best served with soft washing:
Before you start cleaning the roof with any type of solution or even water, it’s good to pre-soak the vegetation around your gutters and other places where the water will flow off of the roof.
If you’re using chemicals, this will also help to keep your plants from absorbing those chemicals and dying.
Working with a pump sprayer is most common for small roof cleaning jobs, and it seems to get the job done well.
You’ll want to mix the chemicals at a 50/50 ratio of chemicals to the water. You can find roof cleaning chemicals on Amazon and in most hardware stores.
When your chemicals are mixed, start high on the roof and work your way downwards towards the bottom. This will help use fewer chemicals because they’ll clean the roof as they roll down it.
When you’re trying to figure out how to clean roof shingles, it’s important to note that you might have to go over some spots more than once, but it’s better to do the whole roof from top to bottom at least once first.
It’s easy to get carried away with the mixture because it’s hard to tell how much you’re putting down. But less is always more when you’re starting.
It’s better to come back later and add more than flush out the whole area around your home with harsh chemicals.
When you’re finished with the whole roof, you might find a few different areas that still have moss attached. This is especially common when working with asphalt shingles.
All you need to do is repeat the process but only on the area that needs more cleaning—no sense in going over the whole roof again.
When you’re finally finished, be sure to re-soak and water the plants and grass around your roof to dilute any of the chemicals more.
If you do it right, you won’t need to worry about the plants dying off or having any problems at all.
Once you’ve mastered how to clean roof shingles, the next step is to ensure those unsightly stains don’t return. Preventing future growth is a crucial part of long-term roof care, and it starts with a proactive approach. Regular roof maintenance is a must, as it creates an environment where algae and moss can’t thrive.
The goal of learning how to clean roof shingles is to protect your investment and maintain your home’s curb appeal. While a DIY approach can be effective for simple tasks like removing light algae or a routine rinse, it’s crucial to recognize the limits of a home project. If you’re dealing with extensive mold growth, a steep roof pitch, or persistent stains that a simple cleaning can’t fix, it’s a clear sign that you need to ask for help to avoid costly mistakes and personal injury.
When the job is too big or too complex to handle on your own, trust the professionals at K&D Roofing. Our team is equipped with the right safety gear and specialized soft-washing equipment to deliver a thorough, damage-free clean that will restore your roof’s beauty and integrity. Don’t take a risk with your most important asset. Reach out to the K&D team for professional and fast service for your roof!