Roof cleaning cost calculator

How much should roof cleaning cost?

Most US homeowners pay between $0.30 and $0.72 per square foot to soft-wash a residential asphalt-shingle roof in 2026. A typical 1,500–3,000 sqft roof lands in the $450–$2,160 range depending on pitch, access (one- or two-story), and how heavy the algae streaking is. The calculator below applies your exact sqft, intensity, and ZIP code's regional cost-of-living band — the pre-selected Soft wash intensity is right for almost every residential roof, because high-PSI water strips asphalt-shingle granules and voids most shingle warranties.

What changes a roof cleaning quote

Roof material — and why high-pressure is almost never the answer

Asphalt shingle (~80% of US residential roofs) requires soft-wash only — a low-PSI mix of sodium hypochlorite, water, and surfactant. High-pressure water strips the protective granules off the shingles and voids most manufacturer warranties (CertainTeed, GAF, and Owens Corning all flag pressure washing as warranty-voiding). Metal roofs tolerate higher PSI but rarely need it. Concrete and clay tile roofs need soft-wash plus careful foot placement — tiles crack under a person's weight. Cedar shake needs specialist chemical-only cleaning.

Algae streaking — the #1 reason for cleaning

The black streaks on asphalt-shingle roofs are Gloeocapsa magma, a cyanobacteria that feeds on limestone filler in shingles. It thrives in humid regions (Southeast US, Pacific Northwest, Mid-Atlantic) and accelerates shingle degradation by retaining moisture. A soft-wash treatment kills the algae and usually clears streaks within 1–3 weeks (the rain rinses off the dead biology). Light streaking maps to the calculator's Standard intensity equivalent; heavy streaking with visible green moss or lichen patches is Heavy.

Pitch and access — the hidden surcharge

The calculator does not bake in pitch or access surcharges, but most operators do. Steep roofs (8/12 pitch and above) typically add 20–35% because the operator either rigs safety lines or works from a ladder/lift. Two-story roofs add another 15–25% over single-story for the same reason. A 2,000 sqft single-story 4/12 ranch is the cheapest scenario; a 2,000 sqft two-story 10/12 Victorian is the most expensive. Ask the operator to itemize.

How long roof cleaning lasts

A properly soft-washed roof stays algae-free for 2–4 years in humid regions and 5–7 years in dry regions. Pacific Northwest and Southeast homes often re-wash every 2–3 years; Southwest and Mountain West homes can stretch to 5+. Zinc strips installed along the ridge after cleaning extend the interval by 2–3 years because zinc kills the algae as rain washes over it.

Why DIY-ing a roof clean is a different decision than a driveway

Driveway DIY is a time-vs-money tradeoff. Roof DIY is a safety tradeoff. Falls from roofs are the #1 cause of fatal home-improvement accidents per the CDC. Soft-wash requires walking the roof or rigging long-reach equipment — and the slick algae you're cleaning makes the surface even more dangerous. Hiring a properly insured pro is essentially always the right answer for residential roof cleaning. Check that the operator carries general liability, workers' comp (or a sole-proprietor injury rider), and ideally roof-specific fall-protection training.

Signs your roof needs cleaning

Black streaks running vertically down north-facing slopes are the classic algae signal. Green or fuzzy moss patches, especially on north sides or under tree drip lines, indicate moss colonization — moss roots actually pry shingles apart and warrant immediate cleaning. White or pale-green spotting is lichen, which is the hardest to remove and the most damaging to the shingle. If you see any of these, the roof is overdue. Clear-but-aged shingles without visible biology can wait.

Regional cost-of-living impact

Roof cleaning labor scales with regional cost of living, same as every other surface. A 2,000 sqft asphalt-shingle roof with soft wash costs roughly $570 in Atlanta (0.95× multiplier), $810 in San Francisco (1.35×), and $840 in Manhattan ZIP 100xx (1.40×). The calculator applies your ZIP's USPS-prefix-based regional multiplier automatically.

Frequently asked questions

How much does it cost to clean a roof?: Most US homeowners pay between $0.30 and $0.72 per square foot for residential asphalt-shingle soft-wash roof cleaning in 2026. A typical 2,000 sqft roof lands in the $600–$1,440 range before pitch and access adjustments. Steep roofs (8/12+) and two-story roofs typically add 20–35% on top. The calculator above shows the per-sqft band before those adjustments.
Should I pressure wash my asphalt shingle roof?: No. High-pressure water strips the protective granules off the shingles and voids most manufacturer warranties (CertainTeed, GAF, Owens Corning all flag pressure washing as warranty-voiding). Use soft-wash — low-PSI water plus a sodium hypochlorite mix — which kills algae and lichen without surface damage. The calculator pre-selects Soft wash intensity for this reason.
How do I know if my roof needs cleaning?: Black streaks running vertically down north-facing slopes are the classic algae signal (Gloeocapsa magma). Green or fuzzy moss patches indicate moss colonization — these are urgent because moss roots pry shingles apart. White or pale-green spots are lichen, the hardest type to remove. If you see any of these, the roof is overdue. Clear shingles without visible biology can wait.
How long does roof cleaning last?: A properly soft-washed roof stays algae-free for 2–4 years in humid regions (Southeast, Pacific Northwest, Mid-Atlantic) and 5–7 years in dry regions (Southwest, Mountain West). Zinc strips along the ridge after cleaning extend the interval by 2–3 years.
Is it safe to walk on the roof for cleaning?: Falls from roofs are the #1 cause of fatal home-improvement accidents per the CDC. The slick algae you're cleaning makes the surface even more dangerous. Soft-wash requires walking or rigging long-reach equipment. Hire a properly insured pro — confirm they carry general liability, workers' comp (or a sole-proprietor injury rider), and ideally roof-specific fall-protection training.
What's the difference between soft-wash and pressure-wash for roofs?: Pressure-wash uses high-PSI water (~1,500–3,000 PSI) for hard surfaces like concrete. Soft-wash uses low-PSI (~100–500 PSI) plus a cleaning solution — usually sodium hypochlorite plus a surfactant — to kill biology without surface abrasion. For asphalt shingles, tile, and cedar shake, soft-wash is the only correct method. Metal roofs tolerate moderate pressure-wash but rarely need it.
Will roof cleaning damage my shingles?: Soft-wash with the correct chemistry and PSI does not damage asphalt shingles. The risks are (a) high-pressure water stripping granules, (b) overly strong sodium hypochlorite damaging plants or siding below if not rinsed, and (c) the operator walking on brittle or old shingles in the wrong conditions. A trained operator manages all three. A reputable pro will pre-wet plants, tarp downspouts, and avoid walking on heat-softened shingles mid-day in summer.
Is this a quote I can hold an operator to?: No — it's an estimate based on industry benchmarks for the soft-wash portion only. It doesn't include pitch/access surcharges, zinc strip add-ons, or chemistry premiums for cedar shake. Use it to know what's reasonable per square foot; confirm the full quote (with adjustments itemized) with the contractor before booking.

Other surfaces?

Same engine, surface-specific copy: driveway, deck, fence, or patio.