Deck washing in Niagara Falls, done at the right pressure.

A practical guide to deck washing in Niagara Falls: what cleaning method is right for cedar, composite, and pressure-treated wood, and straight answers to the questions most homeowners have before booking. Honest ranges, no fabricated numbers.

Why Niagara Falls deck washing requires local knowledge

Niagara Falls sits in damp lake-and-river air, which is harder on outdoor wood than drier inland areas. Algae and grey-out show up faster here, especially on the shaded side of a deck that never fully dries. Most deck cleaning guides skip the step that matters most: matching the cleaning method to the material. Cedar is soft enough that its own trade association, the Western Red Cedar Lumber Association, recommends against power washing it at all; a pressure washer can seriously damage the surface, and soap-and-water or diluted-bleach scrubbing does the job without that risk. Composite decking is brand- and generation-dependent: some current-generation capped composite lines explicitly allow pressure washing up to a stated PSI without voiding the warranty, while older, uncapped composite generally does not, so check the deck's own manufacturer care guide before reaching for a pressure washer.

Wastewater: what a contractor is required to do with it

Deck-wash rinse water, carrying soap, algae or mould treatment, or lifted grime, does not count as "uncontaminated water" and may not lawfully be discharged to a storm sewer. The Regional Municipality of Niagara's By-law No. 2024-51 (in force since 2024-08-29, covering Niagara Falls and every other Niagara municipality) bars a storm-sewer discharge unless it is uncontaminated water, and separately bars any discharge showing visible film, sheen, or discolouration, or a pH outside 6.0 to 9.0: a real second trap, since alkaline algae/mould treatments and many composite-deck cleaners can push past pH 9.0. An individual convicted faces a fine of not more than $10,000 for a first offence and $25,000 for a subsequent offence; a corporation faces up to $50,000 for a first offence and $100,000 for a subsequent offence. Ask any contractor how they contain or divert wash water before it reaches a catch basin: tarping or damming the runoff is the correct answer; no plan at all is worth a follow-up question.

A note on how this guide works

This guide is published by Living Websites, a Niagara-based web-services company. The information here draws on publicly available knowledge about deck washing practice and typical Ontario contractor pricing. It is not affiliated with any specific deck washing service or contractor, and it publishes no price for the work.