Roof Cleaning Cost: Your Material Picks the Method and the Price
Roof cleaning costs $175 to $1,300 in the United States, with a typical 1,500 square foot job landing near $600. The pricing is simple once you see the logic: contractors quote per square foot, and the rate depends on the cleaning method. What most quotes do not say out loud is that your roofing material, not your budget, decides which method is allowed.
What roof cleaning costs in 2026
Roof cleaning cost in the United States lands between $175 and $1,300, and the three major cost guides agree more than they disagree once you account for roof size.
- This Old House: $0.20 to $0.70 per square foot, or $300 to $1,050 for a 1,500 square foot roof, averaging $675.
- Fixr: a national average of $612, a typical range of $450 to $700, a low end of $173 for a chemical clean of a small 200 square foot roof, and a high end of $1,326 to soft wash 1,500 square feet.
- HomeAdvisor: $296 to $625 for pressure cleaning, averaging $461, with the full spread running $150 to $1,000.
Note one thing before you do the math on your own house: your roof is bigger than your floor plan. Overhangs and pitch add surface area, so a 1,500 square foot home does not have a 1,500 square foot roof. Contractors measure the roof, not the house.
Price per square foot by method
Every guide prices by method, and the rates line up closely across sources.
| Method | Price per square foot | What it actually does |
|---|---|---|
| Blower cleaning | $0.05–$0.10 | Clears loose debris only, no stains |
| Zinc oxide application | $0.05–$0.15 | Prevents moss rather than removing it |
| Chemical wash | $0.20–$0.30 | Kills algae and lichen over several days |
| High pressure wash | $0.20–$0.70 | Fast, and damaging to most materials |
| Low pressure wash | $0.30–$0.70 | Under 1,000 psi with detergent |
| Soft wash | $0.30–$0.75 | Under 100 psi plus solution and hand work |
Soft wash is the most expensive line on that list because it is the most labor intensive, not because the chemicals cost more. At roughly 100 psi it is about the pressure of a garden hose, so the cleaning comes from solution dwell time and manual scrubbing. This is where roof work parts company with ordinary power washing, which relies on pressure to do the work.
Your material has already chosen for you
Here is the part that turns a confusing quote into an obvious one. Both This Old House and Fixr map materials to methods the same way, and the mapping is not a preference.
| Roof material | Recommended method | Price per square foot |
|---|---|---|
| Asphalt shingles | Soft wash | $0.30–$0.75 |
| Clay or concrete tile | Soft wash | $0.30–$0.75 |
| Slate | Low pressure | $0.30–$0.70 |
| Wood shakes or shingles | Low pressure | $0.30–$0.70 |
| Metal panels | High pressure | $0.20–$0.70 |
| Rubber membrane | Chemical wash | $0.20–$0.30 |
| Tar and gravel | Chemical wash | $0.20–$0.30 |
High pressure washing runs 1,300 to 2,800 psi. On asphalt shingles and clay tile that is destructive, and This Old House notes it can void a roof warranty. Metal is the one common material built to take it. So if you have asphalt shingles, the cheap $0.20 per square foot high pressure quote is not a bargain you are being offered; it is a quote for the wrong job.
What pushes the number up
Three multipliers do most of the work on the final invoice. Pitch adds up to $0.15 per square foot for extra safety equipment on steep roofs. Height adds about $0.10 per square foot for each story above the first, moving the typical rate from roughly $0.40 on a one story house to $0.60 on a three story one. A Pennsylvania contractor publishes the same logic as explicit multipliers: a base of $300 to $450 for asphalt shingles, plus 15 percent for a medium pitch, 30 percent for steep and 50 percent for extreme, plus 20 to 40 percent for larger roofs.
Moss is the other variable, and it is regional. Nationally, removal is folded into a standard clean at $0.20 to $0.70 per square foot, with a prevention treatment running $100 to $250. In the wet Pacific Northwest, where moss is the main reason anyone calls, a Portland area specialist sells moss removal as a flat package starting at $695 and a basic moss treatment starting at $225. If you live where moss grows year round, budget against the regional package price, not the national average.
Is your quote reasonable?
Ask the contractor for two numbers rather than one: the measured roof area and the rate per square foot. If they will only give a lump sum, that is the first thing to push back on. Then check it against the method your material requires. On a 2,000 square foot asphalt shingle roof, a soft wash at $0.30 to $0.75 per square foot means $600 to $1,500, and a quote of $350 almost certainly means someone plans to point a pressure washer at your shingles.
Two more checks. If the quote is hourly rather than by area, HomeAdvisor puts the going rate at $35 to $80 per hour, and This Old House notes some crews bill $17 to $36 per hour; anything well above that band needs justifying. And ask what the quote excludes. Stain removal commonly adds $50 to $100, a silicone sealant runs $1 to $5 per square foot, and gutter cleaning is usually billed separately at $0.70 to $1.30 per linear foot. Bundling those on one visit is cheaper than booking a second trip, but only if you know they are extras before you sign.
On timing, plan for a clean every two to five years. Moss holds moisture against the roof surface, which is what shortens shingle life, so in a damp climate the shorter end of that interval is the cheaper choice over the life of the roof.
Last updated: October 2026