We're not anti-DIY — but rental pressure washers can do real damage in inexperienced hands. Here are the five mistakes we see most often.
1. Spraying siding at full pressure
Vinyl, wood and stucco aren't designed to take a focused 3,000 PSI stream. You'll force water behind the siding, blast holes in soft wood, and crack stucco.
2. Aiming up under siding overlaps
Water gets driven up under the laps and into wall cavities, soaking insulation and framing. The damage shows up months later as mold inside the walls.
3. Pressure washing your roof
This is the fastest way to void a shingle warranty. Granules tear loose, the underlayment gets exposed, and leaks follow.
4. Skipping cleaning solution
Pressure rinses dirt — it doesn't kill mildew or algae. Without proper detergent, the green stuff is back within weeks.
5. Working on a ladder with a wand
Recoil on a pressure wand can knock a person clean off a ladder. Every season, ER visits spike from exactly this.
The takeaway
For driveways and patios? Renting a unit can work. For siding, decks, roofs and anything you'd hate to replace — call a pro.
— The Louisville Housewash Crew
