DIY Pressure Washing: 6 Ways It Damages Homes

1. Water forced behind siding

Spraying upward at vinyl siding drives water behind the panels, where it can soak sheathing and insulation and lead to mold inside walls.

2. Gouged and fuzzy wood

Wood decks and fences are softer than they look. Too much pressure or holding the tip too close raises the grain, leaves wand marks and ruins the surface for stain.

3. Etched concrete and zebra stripes

A narrow nozzle can etch lines into concrete, and sweeping a wand back and forth leaves uneven stripes. Pros use rotary surface cleaners for an even finish.

4. Stripped paint and damaged mortar

High pressure can peel paint and wash out mortar joints in brick, leaving repair work behind.

5. Broken windows, seals and screens

Direct spray can crack glass, blow out window seals, tear screens and force water into light fixtures and outlets.

6. Injuries and ladder falls

A pressure washer's jet can cause serious injuries, and the kickback on a ladder is a common way people fall. Second stories and roofs aren't DIY jobs.

And it often doesn't work

Pressure alone doesn't kill algae and mildew, so DIY-cleaned siding often turns green again within months. Professionals use soft washing solutions that kill growth at the root.

When DIY is fine

Small jobs like patio furniture, trash cans or a small concrete pad on low settings are reasonable DIY. For siding, roofs, second stories, wood and large driveways, a professional is safer and usually cheaper than repairs.