Pressure Washing Your Home Exterior in Ontario
Ontario's climate — wet springs, humid summers, and long winters — creates the conditions for significant exterior dirt, moss, algae, and mildew accumulation on home surfaces. Annual or biannual pressure washing is standard maintenance for Ontario homes with vinyl siding, concrete driveways, and wood or composite decks.
Best Season to Pressure Wash in Ontario
Spring (late April through June) is the primary pressure washing season in Ontario — after the winter grime has accumulated and before summer heat makes working conditions uncomfortable. Fall (September–October) is the secondary window for homeowners who want to clear summer algae from decks and prepare the exterior before winter. Avoid pressure washing when temperatures are below 5°C — water freezes in crevices and causes damage.
Surface-Specific Guidelines
- Vinyl siding: 1,200–1,500 PSI, wide fan tip, top to bottom. Never spray upward under the panels (forces water behind the siding).
- Brick: 1,500–2,000 PSI maximum. Avoid mortar joints — high-pressure water erodes mortar over time. Spot-test first.
- Wood decks: 500–800 PSI maximum (low pressure). High pressure splinters and damages wood grain. A deck cleaner chemical combined with low-pressure rinsing is safer than high-pressure alone.
- Concrete driveways: 3,000+ PSI acceptable. Turbo nozzle significantly speeds cleaning. Pre-treat oil stains with a degreaser before washing.
- Composite decking: Follow manufacturer guidelines — most composite decking can tolerate moderate pressure but not high-pressure point nozzles.
What to Avoid
Never pressure wash: windows (water under seals), doors (especially weather-stripped entry doors), electrical panels or outlets, or painted surfaces with failing paint (the pressure will accelerate peeling). Do not aim at any vent, soffit, or gap where water can enter the building envelope.