House Washing Cost on Long Island (2026)
Most Long Island house washes run between $350 and $850. Here's what drives the number up or down, and what "too cheap" actually means for your siding.
Typical ranges by home size
1,500 sq ft ranch (single story): $350 to $475. Usually one wash day, one tech or a two-person crew for a half day.
2,000 to 2,500 sq ft colonial (two story): $475 to $650. Standard crew of two, half day to full day depending on access.
3,000+ sq ft colonial, Victorian, or waterfront: $650 to $950. Full crew, ladders, sometimes a lift.
Detached garages, sheds, and pool houses add $75 to $175 depending on size.
What drives the price up
Heavy algae or mold: anything visibly green or black adds time and chemistry. Add 10 to 20 percent.
Gutter brightening: oxidation streaks on white aluminum gutters require a separate acid treatment. Add $100 to $250 depending on linear feet.
Cedar shake, wood siding, or stained surfaces: need gentler chemistry, more rinse time, and owner-approved test patches. Add 15 to 25 percent.
Second-story access over decks, AC units, or landscaping: adds ladder time. Add $50 to $150.
What "too cheap" means
If someone quotes you $200 for a two-story colonial, they are either skipping insurance, skipping biocide, or planning to high-pressure the siding and leave. Any of those three is a real cost to you later, it just doesn't show up on the invoice.
A properly-insured Long Island crew with commercial equipment, PWNA-grade chemistry, and a real warranty cannot profitably do a full house wash for under $350. Math doesn't work.
What's included in a real quote
Full house soft wash with biocide, deck or walkway rinse-down if overspray reached them, gutter face brightening if visibly streaked, plant cover-down and pre-rinse, and a walk-through with you before the crew leaves. If any of those aren't in writing, they're not in the job.