A mossy, shingled roof

Roof Cleaning &

Moss Treatment

Seattle Window Cleaners protects the life of your roof.

About Our Roof Cleaning Service

Moss and algae are common issues for residential roofs in the greater Seattle and Bellevue areas. Moss, in particular, can lead to the deterioration of your sub-roofing, damage your shingles, and lead to more extensive water damage that can be more costly than simply taking care of them with regular maintenance and cleaning.

Roof Cleaning & Moss Treatment

With our recommended annual roof cleaning service, our skilled technicians will expertly remove loose debris and apply Zinc to prevent and deter moss growth. The natural Zinc activates when it comes into contact with rainwater, penetrating the roof moss and effectively eradicating it. This service is particularly effective for addressing light moss growth and serves as an excellent preventive measure for ongoing maintenance.

A roof completely overtaken by aggressive moss
A roof that has been professionally cleaned

Our Roof Cleaning & Moss Treatment Approach

Essentials of Roof Cleaning: Our roof cleaning service is designed to meet various needs and comes in tiered packages. The basic package includes the removal of loose debris and the application of MossOut to eliminate and prevent minor moss growth.

Comprehensive Moss Removal: For more extensive cleaning requirements, especially if moss growth is visibly prominent from the ground, we recommend a more thorough procedure. This involves the removal of all loose debris, followed by the application of a biodegradable softwash solution to the entire roof. This treatment is highly effective against moss growth and provides long-lasting prevention.

Ground Cleanup: In every roof and gutter cleaning package we offer, ground cleanup is an integral part of the service scope.

How to Get Started


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Schedule Your Service

Once you have your quote, easily book your preferred service date and time.

Frequently Asked Questions

Why is it important for me to have my roof cleaned?

Extend the lifespan of your roof: Regular roof cleaning is essential for maintaining your home's integrity and extending your roof's lifespan. Debris, dirt, and pollutants can accumulate on your roof over time, leading to damage and deterioration of the roofing materials. Professional roof cleaning services can help remove these contaminants and prevent further damage to your roof.

Prevent mold and algae growth: Moisture and debris on the roof can create a breeding ground for algae and mold, which can cause damage to the roofing materials and lead to health problems for you and your family. Professional roof cleaning services can help eliminate mold, algae, or moss that may be growing on your roof.

Save money on repairs: Regular roof cleaning can help minimize or eliminate damage caused by debris, mold, and algae, which can lead to expensive repairs and shorten the life of your roof. By investing in professional roof cleaning services, you can save money on repairs in the long run.

Improve energy efficiency: A dirty roof can absorb more heat from the sun, which can increase the temperature inside your home and cause your air conditioning system to work harder. Professional roof cleaning services can help cool your home and save energy costs.

Ensure safety: Cleaning a roof can be dangerous, especially if you don't have the proper equipment or training. Professional roof cleaning services have the necessary equipment and expertise to safely and effectively clean your roof without risking injury to yourself or damage to your property.

How often should I get my roof cleaned and undergo moss treatment?

Generally, it is a good idea to get your roof cleaned at least once a year. The frequency of roof cleaning varies depending on the ff. factors:

  1. Type of roof: Different types of roofs require different cleaning frequencies. For example, metal roofs require cleaning every 1-10 years, while tile roofs should be cleaned every 6 months to 5 years.
  2. Age of the roof: Older roofs are generally more susceptible to damage and debris buildup. They require more frequent inspections and possibly additional cleaning.
  3. Environmental factors: Homes in tropical areas, near beaches, production facilities, warehouses, busy roadways, and airports, and homes near lots of mature trees might need more consistent roof cleaning.
  4. Moisture: High humidity or frequent rainfall can encourage moss, mold, and algae growth on the roof, which can cause premature roof failure.
  5. Snow and wind storms: A snowy winter, an intense wind storm, or damage to your roof from a fallen tree or branch may require more frequent roof cleanings or extra roof maintenance than normal.

Do you cater to all types of roofs, including metal and cedar shake roofs?

At Seattle Window Cleaners, we service a variety of roof types. However, there are certain roofing materials and pitches we typically avoid due to safety and expertise concerns.

  1. Metal Roofs: Due to their slippery nature when wet, metal roofs can pose a safety risk for our technicians. Although we generally do not clean these roofs, we might consider exceptions on a case-by-case basis, ensuring the safety and feasibility of the cleaning process for each unique situation.
  2. Cedar Shake Roofs: These roofs require specialized care and techniques to prevent damage. Given that such expertise is currently outside our service range, we do not offer cleaning for cedar shake roofs.
  3. Roofs with a Pitch Steeper Than 6/12: We avoid cleaning these roofs to ensure the safety of our team. Our utmost priority remains the safety and well-being of our technicians, allowing them to provide top-quality service without compromising their safety.

Which areas or locations do you serve for roof cleaning & moss treatment?

We provide roof cleaning and moss treatment services throughout the Seattle region, covering areas like West Seattle, Burien, Mercer Island, and Capitol Hill. Additionally, we cater to residents in Bellevue. If your location isn't mentioned, please reach out. We always aim to accommodate as many areas as possible.

How much does roof cleaning and moss treatment cost?

The cost of roof cleaning depends largely on the size of the area you’d like to be cleaned, and the types of gutters. You can get a quote (price included) for roof cleaning services on our website. Our website has an application that will ask you a few short questions about your home, and then provides you with an instant quote. Our roof cleaning services are typically offered in tiered packages and you can schedule yourself online on our calendar.

Why Choose Seattle Window Cleaners


Experienced Professionals

Boasting over 12 years of expertise, our team has been diligently serving homes across Seattle and Bellevue.


Reliable Service

We show up on time and perform the services we said we would do, at the price agreed.

safe cleaning and great results

Safe and Effective Cleaning

Trust in our methods. We prioritize safety, ensuring impeccable cleaning without risking damage to your property.

locally owned and operated

Fully Credentialed

We're not just professionals; we're licensed, bonded, and insured for your peace of mind.

happy customers

A Legion of Happy Customers

Join our growing list of over 10K satisfied customers. Your satisfaction is our success.

Trusted By Clients on

Since 2008

5 gold stars

West Seattle Window Cleaner did a great job in and out. They removed all the screens and replaced them, were careful inside, and were well worth the money.

Gary L.
5 gold stars

Very professional and friendly. They did an excellent job and will definitely hire them again in the future.

Megan E.
5 gold stars


Arlene G.
5 gold stars

They were courteous, on-time and our windows look amazing!

Holly W
5 gold stars


Karen R.
5 gold stars

The window cleaners were very professional and very nice. This company is reasonably priced. They did not even mind my dog who followed them around. They did a great job and I will hire them again.

Mia D.