How Much Does Roof Cleaning Cost in Washington State?
Your roof faces a lot of challenges in Washington State. In fact, parts of Washington see over 150 days of rain every year, and that moisture creates the perfect environment for algae, lichen, and moss. Each year, hundreds of homeowners in Seattle, Tacoma, Kitsap County, and Silverdale deal with costly repairs that could have been avoided.
According to local estimates, moss-related roof issues raise repair costs by up to 30%.
You might think your roof needs replacing, but it often only needs a professional cleaning. The decision to get your roof cleaned can save thousands of dollars on roof replacement. But before making the call, one big question usually comes up.
How much does roof cleaning cost in Washington State?
This post covers everything you need to know. You’ll see average costs and what drives prices up or down.
Average Roof Cleaning Costs in Washington State
In Washington State, local roof cleaning costs typically range between $300 and $900, with an average of around $750. This range accounts for factors like roof size, material, and the chosen cleaning method.
Roof Cleaning Cost per Square Foot
Professional roof cleaning services in Washington generally charge between $0.20 and $0.70 per square foot. The specific rate depends on the roof’s material and the cleaning technique employed.
Roof Cleaning Price Comparison Table
| Roof Size (sq. ft.) | Estimated Cost Range |
| 1,000 | $200 – $600 |
| 1,500 | $300 – $900 |
| 2,000 | $400 – $1,200 |
| 2,500 | $500 – $1,500 |
| 3,000 | $600 – $1,800 |
These estimates provide a general idea of potential costs, but actual prices may vary based on specific circumstances.
What Factors Influence the Cost of Roof Cleaning in Washington State?
Roof cleaning prices rarely follow a flat rate. Professionals look at multiple details before giving a final number. Some of these details carry more weight than others. Let’s explore what affects the cost in Washington State.
Roof Size and Complexity
You should start with the most obvious factor: the roof size. A small, single-level roof takes less time and fewer resources, keeping the price lower. Now, what if you have a large multi-section roof with peaks, valleys, and hidden corners? Cleaning that takes longer, and crews often need special ladders or gear, leading to a higher bill.
- A 1,000-square-foot roof may cost near $350
- A 3,000-square-foot roof with complex angles may reach $1,000 or more
The larger the roof, the more surface area to cover. That adds time, labor, and cost.
Roof Material
The type of roofing material affects the cleaning method and, consequently, the cost. Asphalt roof shingles often require soft wash roof cleaning, costing approximately $0.15 to $0.60 per square foot. Metal roofs may be suitable for low-pressure washing, with costs ranging from $0.20 to $0.70 per square foot . Delicate materials like slate or wood shakes necessitate specialized care, potentially increasing the price.
- Asphalt shingles absorb less moisture, so they cost less to clean
- Metal roofs resist mold, but slippery surfaces call for more caution
- Tile or slate roofs crack under too much pressure, so professionals take slower, more careful steps
Different materials demand different techniques. That’s why roof type plays a key role in the total cost.
Roof Pitch and Accessibility
A steep roof doesn’t allow easy movement, so safety ropes, extra labor costs, and special equipment are needed. If your home has a high slope or tall peaks, expect a higher price. The roof cleaning company may need more time and safety checks before the job of cleaning your roof even begins.
Flat or gently sloped roofs are easier to access, as that reduces labor, which helps control the overall cost.
- Steep angles add time
- Multi-story homes require more setup
- Limited access adds complexity
The Extent of Roof Cleaning Work Required
Some roofs only need a basic rinse to remove dust. Others hold layers of moss, algae, or even lichen. These organic growths attach deep into the material. They demand more effort, stronger treatments, and repeat passes.
- Light debris means faster work and lower cost
- Moss-covered roofs need full moss removal service and surface protection
- Algae streaks take longer to treat and rinse
Additional Cleaning Services
Many homeowners pair roof cleaning with other services. That makes sense. Once the crew sets up, adding tasks like gutter clearing or siding washing saves time.
- For professional gutter cleaning service, expect to pay $100 to $300
- Moss prevention treatment can add $100 to $350.
Combined in one visit, these extras provide better value than booking separate appointments.
Common Methods to Clean Your Roof and Their Average Costs
In Washington State, the selection of an appropriate roof cleaning method depends on the material, condition, and specific requirements of the roof. Each method presents distinct approaches and varying costs. A thorough understanding of these options enables homeowners to make informed decisions regarding roof maintenance.
Soft Washing
Soft washing employs a low-pressure water spray combined with specialized cleaning solutions to remove dirt, algae, and mildew. This method is gentle on roofing materials, making it suitable for asphalt shingles, clay tiles, and cedar shakes. The cleaning solutions used in soft washing not only clean but also inhibit the future growth of unwanted organisms.
- Cost of soft washing: Typically ranges from $0.30 to $0.75 per square foot.
Pressure Washing
Pressure washing utilizes high-pressure water to eliminate grime, moss, and debris. While effective, high-pressure washing can be harsh on certain roofing materials and may damage your roof if not executed properly. Pressure washing service is Rarely recommended, but if so it’s for durable surfaces like metal roofs. Again not recommended.
- Cost of pressure washing: Generally falls between $0.20 and $0.70 per square foot.
Chemical Treatments
Chemical treatments involve applying specialized and safe cleaning agents to eradicate moss, algae, and lichen. These treatments are particularly useful for roofs with persistent biological growth. The chemicals used are designed to penetrate and kill the organisms, preventing regrowth.
Cost of chemical treatments: Typically ranges from $0.20 to $0.30 per square foot.
| Cleaning Method | Suitable Roof Types | Pros | Cons | Average Cost per Sq. Ft. |
| Soft Washing | Asphalt, Clay, Cedar | Gentle on materials; prevents regrowth | May require more time to see results | $0.30 – $0.75 |
| Soft Washing | Metal | Quick removal of debris | Risk of damage to delicate materials | $0.20 – $0.70 |
| Chemical Treatment | Various (with biological growth) | Effective against moss and algae | May need multiple applications | $0.20 – $0.30 |
Choose Johnny Tsunami For a Professional Roof Cleaning Service
As a leading exterior cleaning company, Johnny Tsunami has cleaned thousands of roofs across Seattle, Tacoma, and Kitsap County. Our professional roof cleaners know local roof types, understand how moss grows in damp zones, and follow proven processes that remove grime without harming materials.
Johnny Tsunami uses biodegradable solutions to protect landscaping, preserve roof coatings, and meet environmental safety standards. Clean surfaces matter, but so do clean soil and air around your home.
Reach out to us today to schedule your exterior cleaning services. Let our roof cleaning experts take care of your roof cleaning and maintenance the right way. Call now or request a free quote online.
