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.

Key Takeaways

  • Protect Your Roof: Learning how to clean roof shingles is essential for protecting your home. A clean roof not only enhances curb appeal but also extends its lifespan by preventing damage from algae and moss.
  • Soft Washing is Key: For most roofing materials, soft washing is the recommended method. It uses low pressure and is much safer than traditional power washing, which can damage shingles and void a warranty.
  • Proactive Prevention: After you learn the essentials of how to clean roof shingles, you should focus on prevention. Techniques like installing zinc strips, trimming tree branches, and ensuring proper attic ventilation are crucial for stopping future growth.
  • Know When to Call a Pro: While many cleaning tasks can be done yourself, a professional is the safest and most effective option for steep roofs, extensive stains, or complex projects.

Why It’s Important to Know How To Clean Roof Shingles?

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 learn how to clean roof shingles is to extend its life. The cleaner the roof is, the longer it will last and provide better protection for your home.

Let's tackle the question of how to clean roof shingles with this Navy blue vintage building with white trim and dark roof shingles.

Signs Your Roof Needs to Be Cleaned

If you’re wondering whether or not your roof needs to be cleaned, then it likely does. The first step during the process of how to clean roof shingles is to find out if your roof have stains, streaks, or other abnormal colors that give you an indicator if it needs maintenance.

Beyond looking just for discoloration, also take the time to schedule a roof inspection of the shingles up close to ensure that there aren’t any algae or moss growing on your roof.

How to clean roof shingles from debris, moss, or algae growth.

Common Types of Roof Algae

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 learn how to clean roof shingles right away.

Fire Moss

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.

how to clean roof shingles that are grey bitumen asphalt overgrown with green moss

Gloeocapsa Magma

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.

Soft Washing vs. Pressure Washing

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.

Materials That Can Be Pressure Washed

Here are the materials that are commonly safe to pressure wash:

  • Brick
  • Concrete
  • Aggregate or Rocks

Most other materials can be damaged in some way if you pressure wash them.

Man worker washing tilted stone roof shingles with water pressure washer

Materials That Should Be Soft-Washed

The below materials are best served with soft washing:

  • Stucco
  • Wood Decking
  • Wood Fencing
  • Wood Siding
  • Asphalt Shingles
  • Cedar Shakes
  • Metal Roofing
As you can see, when answering the question “how to clean roof shingles”, you have learned that most roofing materials will require soft washing, but that doesn’t mean you can only use a hose to clean the roof. There are some cleaning solutions that can help get the job done.

Cleaning Asphalt Shingles: Step-By-Step

1. Set Up and Pre-Soak

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.

person pre-soaking plants before cleaning roof shingles

2. Mix the Chemicals

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.

3. Start High and Work Down

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.

Caucasian man is washing the roof from high to low with washer

4. Don’t Overdo the Chemicals

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.

5. Double Down on Problem Areas

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.

Cleaner with pressure washer at roof of house cleaning the roof tiles and removing moss

6. Re-Soak and Water Plants

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.

young woman watering flowers at garden after cleaning roof shingles

Beyond Cleaning: How to Prevent Future Stains

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.

A List of Prevention Techniques

  • Install Zinc or Copper Strips: Placing these strips along the roof ridge inhibits the growth of algae and moss.
  • Trim Overhanging Branches: This allows sunlight to dry the roof surface and prevents moisture buildup.
  • Keep Gutters Clear: Regularly cleaning gutters prevents water from backing up and creating a breeding ground for organic growth.
  • Ensure Proper Ventilation: Good attic airflow keeps the roof cooler and drier, making it less hospitable to mold and algae.

How To Clean Roof Shingles: When to Ask For Help?

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!