One of the most common roof problems is moss, particularly in damp climates. Moss can be especially damaging to wood and asphalt shingle roofs. However, you can find a bottle of moss killer to stop the problem for an affordable $16–$45.*

Learn which remedy is right for you and how to safely and efficiently eliminate moss in our guide.

*All cost ranges are calculated with average Amazon prices.

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Tools and Materials Needed

Here’s what you’ll need to remove moss from asphalt shingles and most other roofing materials.

Tools Needed

Most homeowners already have many tools they need to safely remove moss, but if you don’t, plan to spend between $330 and $690. Roof safety kits are especially important and usually include a harness, safety rope, and brackets to attach to the roof.

Tool	Cost Range
Ladder	$150–$350
Work gloves	$5–$10
Safety goggles	$10–$15
Garden hose	$20–$50
Spray nozzle	$10–$20
Soft-bristled scrub brush	$8–$20
Long-handled scrub brush	$14–$40
Plastic sheeting	$7–$20
Spray bottle (optional)	$6–$15
Safety harness kit (optional)	$100–$150

Materials Needed

Homeowners need little more than a cleaning solution that targets moss, mildew, and algae to remove moss. You can make your own solution to reduce costs, which we’ll explain in the next section.

Material	Cost Range
Moss cleaning solution	$16–$45
Bleach (optional)	$5–$20

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Steps for Cleaning Moss From a Roof

Follow these steps to remove moss from a roof. Note that not every step is necessary for every homeowner. For example, cleaning too vigorously can damage some roofing materials, so we recommend starting with gentler methods and slowly progressing until you’ve successfully cleared the moss.

If you’re a visual learner or want to get a better understanding of the entire process before starting, check out this how-to video featuring general contractor Tom Silva. In addition to demonstrating how to clean a mossy roof, Tom explains what causes this problem and steps you can take to prevent the moss from coming back.

Step 1: Prepare for Roof Cleaning

First, drape plastic sheeting over any trees or bushes near your home’s sides, particularly if you’re going to use a bleach solution. Next, set up your ladder on level ground and climb up carefully. If the ladder’s top doesn’t attach to the roof, have another adult hold the ladder as you climb. 

Carry tools up the ladder with you in a bag so that your hands are free. If you’re using a safety harness and rope, secure your safety system to the roof as instructed by the manufacturer. Once you’re secure, put on your rubber gloves and safety goggles.

Step 2: Spray the Roof With Water

Gently brush loose moss off the roof with a broom, or use a garden hose and corresponding nozzle to gently spray it off. Start at the roof’s peak and work downward. If you attempt to work upward—against the grain of the roof shingles or tiles—you can damage the roof and actually force moss deeper into the cracks and crevices.

We don’t recommend a pressure washer for this process. Pressure washing will almost certainly damage shingles, strip asphalt shingles of granules, and ultimately weaken the roof’s integrity. 

Step 3: Scrub the Roof To Remove Additional Moss

Remove the remaining moss with your soft-bristle brush or long-handled scrub brush by scrubbing moss from the roof’s peak downward. Gently clean small sections at a time and be especially careful when walking, as a wet roof is slippery.

Step 4: Apply Cleaning Solution

Once the bulk of the moss has been removed, you can apply your moss-removal solution. Premixed liquid cleansers such as Wet & Forget typically come in pump sprayers, but you may need to invest in your own bottle for other solutions. Note that some remedies are sold as dry powder. 

Alternatively, you can mix your own moss killer using items you might already have around your home. For a basic solution, mix 1 to 3 cups of bleach with 2 gallons of water. Some mixes also call for dish soap or vinegar, but these alone are unlikely to kill moss. If you use bleach, be sure to rinse any plants around the base of your home with water before and after applying the solution. This will help prevent the bleach from killing the plants as it washes off your roof.

Neither premixed nor homemade moss-removal solutions work instantly, so apply them to your roof and let them sit for about 20–45 minutes or as long as the manufacturer recommends. You’ll want to choose a cloudy day to remove moss so that the solution doesn’t evaporate before it’s had a chance to do its job.

Step 5: Rinse the Roof With Water (If Necessary)

While powder solutions may not require rinsing to remove, liquid solutions will. Once the solution has taken effect, rinse it off by spraying downward from your roof’s peak. Don’t be discouraged if some moss lingers; part of finishing the job is sometimes manually removing dead moss after applying and removing the cleaning solution.

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How To Prevent Moss on a Roof

Once you’ve cleaned moss from your roof, you can take the following steps to prevent future moss growth.

Step 1: Install Zinc or Copper Strips – Installing metal strips under the top row of shingles will release small metal particles into precipitation that runs down your roof, inhibiting moss buildup. The process will likely cost you between $23 and $80. Copper strips work best, but zinc strips (like the one Tom used in the video above) are a bit less expensive. 

To install, you’ll simply lift up the top row of shingles and secure the metal strip underneath with roofing nails. We recommend completing this step after removing large or loose pieces of moss and before applying a cleaning solution.

Step 2: Prune Tree Limbs – Moss grows most easily on the areas of a roof where moisture is trapped, and overhanging trees can compound the problem by blocking sunlight or bringing damp leaves into contact with shingles. Consequently, it’s a good idea to prune back any tree limbs that hang over your roof.

Step 3: Keep Gutters Clean – Maintaining a working gutter system is important to keep water moving downward and away from your roof. Gutters and downspouts need to remain unobstructed to work correctly, so ensure you clean them thoroughly or hire a specialist to clean them once or twice per year. Installing a top gutter guard may cut down on how often you need to clean gutters, but they’ll still clog over time, so check that rainwater isn’t pouring over the gutters’ edges.

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DIY vs. Professional Moss Cleaning From a Roof

Moss removal is a job you can do yourself, but there are still advantages to hiring a professional.

DIY Moss Cleaning from a Roof

DIY moss removal is fairly easy and requires only basic tools and materials. However, there’s a risk of falling from your roof, especially if it’s wet. Remember that you need to rinse from the top of the roof down, which requires walking on wet shingles. Make sure you don’t compromise your safety in your effort to save money.

Professional Moss Cleaning from a Roof

If you don’t feel comfortable working on the roof or don’t already have the necessary tools, you can hire a professional roof-cleaning service to do the job for you. Moss removal is typically included in the overall cost of a roof cleaning. Professional roof cleaners charge about 30–60 cents* per square foot to soft-wash asphalt shingles.

Note that different roof types require different cleaning methods, and some cost more than others. Prices also vary based on the square footage of your roof. The range listed above works out to $450–$900 for a 1,500-square-foot asphalt shingle roof. If you have a smaller roof or only have moss on part of your roof, you might pay significantly less.

*Costs based on contractor estimates used by Angi, as updated in September 2023.

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How To Save on Cleaning Moss From a Roof

Here’s how to keep moss removal costs down.

• Research the best cleaning methods for your specific roofing materials to avoid causing costly damage.
• If moss is a regular problem, use prevention methods and clean regularly to stop buildup. 
• Hire professional roofers to fix any damage as soon as you spot it, which may prevent moisture from pooling.
• If your asphalt shingle roof is more than 20 years old and nearing the end of how long a roof lasts, consider roof replacement. This will cost more than a roof cleaning but may help prevent moss buildup and improve your home’s resale value.

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How To Hire a Pro

Here’s what to look for when hiring professional roof cleaners.

• No special licensure is required for roof cleaning, but make sure all technicians are bonded and insured to protect yourself from liability in case of a fall.
• Avoid hiring a company that primarily uses pressure washers. 
• Check the company’s Better Business Bureau (BBB) page to see its rating, accreditation status, and handling of customer complaints.
• Ask for references from satisfied customers and consult trustworthy review sites such as Trustpilot and Google Reviews.
• Ask about seasonal or package deals.

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Our Conclusion

The key to removing roof moss is to be careful—both with your own safety and with the roof’s condition. Overly aggressive cleaning can damage certain types of roofing materials, and you don’t want to face the expense of a new roof before you have to. If you hire professional cleaners, we recommend getting quotes from at least three local companies before choosing.

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FAQ About Cleaning Moss From a Roof

What is the best way to remove moss from a roof?

The best way to remove moss from a roof is by rinsing with low-pressure water and using a targeted moss-removal solution.

Is it OK to scrape moss off a roof?

Yes, you can scrape moss off your roof if you work carefully and use materials that will not damage the roof.

What time of year is best to remove moss from a roof?

Summer is often the best time to remove moss, but be sure to read instructions that correspond to your specific solution. Some solutions are activated by rain, while others will be washed away by it.

What does moss on a roof do?

Moss growing in cracks and crevices can loosen and weaken roofing materials. It also traps moisture on the roof, potentially causing water damage.

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