Roof Cleaning Cost Calculator
Estimate the cost to clean and wash a roof from its footprint area and your material (cleaning solution) and labor rates per square foot.
How this calculator works
Roof cleaning is usually priced per square foot of roof footprint, split into a cleaning solution (material) cost and a labor cost. This calculator multiplies your roof’s footprint area by each rate separately, then adds the two together for a total estimated cost.
Formula: Total cost = roof footprint area × material rate per sq ft + roof footprint area × labor rate per sq ft.
Worked example
A 40 ft × 30 ft roof footprint (1,200 sq ft), $0.10/sq ft material, $0.25/sq ft labor:
- Footprint: 40 × 30 = 1,200 sq ft
- Material: 1,200 × $0.10 = $120
- Labor: 1,200 × $0.25 = $300
- Total estimated cost: $420
Notes
Soft washing — a low-pressure application of a cleaning solution rather than a high-pressure blast of plain water — is the recommended method for asphalt shingle roofs. High-pressure washing can strip the granules off shingles, which protects the underlying asphalt from UV damage, so stripping them shortens the roof’s usable life even though the roof looks clean afterward.
Steep or multi-story roofs add cost beyond this base rate. Working safely at height requires harnesses, ladders, roof anchors, or lift equipment, and the work itself moves more slowly and carefully than a simple single-story wash. Expect a contractor’s quote to include an access and safety surcharge on top of the per-square-foot rate used here for roofs that aren’t easily walkable.
How to use
Measure or estimate your roof’s footprint in square feet — length times width of the building’s footprint, not the sloped surface area — then enter a material rate and a labor rate per square foot. The calculator returns the material cost, labor cost, and total, which you can compare against contractor quotes for your roof.
Estimates only. Actual cost depends on your region, roof pitch/height, and degree of staining — get a contractor quote before budgeting.
Frequently asked questions
What counts as the material rate in this roof cleaning estimate?
The material rate covers the cleaning solution used to treat the roof, priced per square foot of roof footprint. It doesn't include equipment rental, water usage, or travel costs, which some companies fold into the labor rate or quote as separate line items.
Why is soft washing recommended over pressure washing for roofs?
Soft washing uses a cleaning solution at low pressure to kill algae, moss, and lichen without physically blasting the surface. High-pressure washing can strip the protective granules off asphalt shingles, which shortens the roof's lifespan, so most roofing professionals recommend soft washing for asphalt roofs specifically.
Does this estimate include gutter cleaning?
No. This calculator prices washing the roof surface itself. Gutter cleaning is typically a separate service with its own pricing, so ask your contractor whether it's bundled into a quote or needs to be added on top of the roof cleaning cost.
Why would a steep or multi-story roof cost more to clean than this estimate?
This calculator uses a flat rate per square foot, but steep pitches and multi-story homes require additional safety equipment, harnesses, and more careful, slower work to access safely. Contractors typically add a surcharge for that extra access and safety burden on top of their base per-square-foot rate.
Estimates only. Verify quantities with your supplier before purchasing.