Pressure washers are fantastic tools for removing grime, mould, dirt, and stains from exterior surfaces. But while they’re great for driveways and patios, not every surface should face the blast of high-pressure water. Misusing a pressure washer can lead to costly damage, structural issues, or injury.
At KBC Services, we help Perth homeowners get the most out of their cleaning efforts—safely and effectively. In this article, we’ll explore what not to pressure wash, the risks involved, and how to protect delicate materials around your property.
Why You Should Be Cautious with Pressure Washers
The average pressure washer emits 1,500 to over 3,000 PSI. That kind of force can cut through grease—and also paint, mortar, or timber if handled poorly. What’s worse, improper use can cause irreversible damage, forcing you to repaint, re-seal, or even replace affected areas.
If you’re unsure which surfaces are pressure-washer safe, it’s always best to consult a professional. Our trained team at KBC Services offers guidance and tailored cleaning across suburbs like Joondalup and Belmont.
Surfaces You Should Never Pressure Wash
1. Asphalt Roof Shingles
Although your roof might seem like a great place to blast away mould or moss, pressure washing asphalt shingles is a huge mistake. High pressure can loosen granules that protect your roof, shorten its lifespan, and void warranties.
Instead, consider Roof Pressure Washing Perth, where KBC uses gentle methods suitable for your roof type.
2. Old Mortar or Crumbling Brickwork
Pressure washers can rip apart the mortar between bricks, especially on older homes. This accelerates structural damage and water penetration.
In suburbs like Osborne Park, where many homes have heritage features, we often recommend soft washing instead.
3. Windows and Glass Panels
Glass might seem like an easy target for a quick clean, but even slight misjudgement in angle or distance can crack or shatter panes. The pressure can also damage the seals and lead to long-term leaks.
Use traditional methods or hire pros who know how to adjust settings safely. KBC Services can handle window surrounds without harming seals.
4. Vehicles and Delicate Paintwork
Even though some people use lower PSI settings to wash their cars, it’s risky. Paint chips, seals degrade, and water gets into electrical components. Unless you have experience with pressure settings and safe distances, it’s not worth the risk.
Stick to hand washing or auto-specific tools instead of a high-powered unit.
5. Electrical Fixtures and Outdoor Power Points
Never use a pressure washer near outdoor lights, power points, or electrical boxes. Water can easily infiltrate seals, resulting in power shorts, corrosion, or fire hazards.
Areas around electrical points should be hand-cleaned or shielded properly before work begins.
6. Wood Decks with Loose Seals or Paint
While wood decks can often benefit from cleaning, you should not use high-pressure settings unless the timber is sealed and structurally sound. Old, splintered, or painted wood can be stripped or gouged.
In shaded suburbs like Dianella, decks tend to grow mildew. We recommend soft-washing to protect the wood.
7. Air Conditioning Units
Blasting dirt off your outdoor AC unit may seem like a time-saver, but water pressure can damage the fins and coils. This reduces performance or may even void your manufacturer’s warranty.
If your unit is visibly dirty, contact your HVAC professional instead.
8. Lead-Based Paint or Asbestos Surfaces
Older homes in areas like Bayswater may still contain lead-based paints or asbestos materials. Pressure washing these surfaces can release hazardous particles into the air, creating serious health risks.
Always seek professional help before attempting to clean any older surface with unknown material composition.
Safe Alternatives for Sensitive Areas
If you’re unsure about whether an area should be pressure washed, consider these alternatives:
- Soft washing: Uses low pressure and specialised detergents
- Hand scrubbing: Ideal for painted or detailed areas
- Eco-safe chemical treatments: For moss, algae, or mildew
- Steam cleaning: Effective for bacteria without abrasive force
At KBC Services, we offer comprehensive Pressure Washing Perth solutions that consider both safety and results. We’ll always assess your property before choosing the right method.
Partner with Perth’s Trusted Pressure Washing Experts
With homes varying widely across Perth’s suburbs—from Landsdale to Wangara—there’s no one-size-fits-all approach. Our team understands the materials and environmental pressures unique to each location.
KBC Services proudly provides safe, effective exterior cleaning solutions across the city. If you’re ready to refresh your home without risking damage, get in touch for a free quote today.
FAQs – What Not to Clean with a Pressure Washer
1. Can I pressure wash painted surfaces like fences or sheds?
Only if the paint is high-quality, bonded, and not chipping. Otherwise, pressure washing may strip it away unevenly.
2. Why is pressure washing glass risky?
The pressure can cause cracks, damage seals, or shatter panes. It’s best to clean glass manually or with specialist tools.
3. Is it safe to pressure wash garden furniture?
It depends on the material. Hardwood or metal furniture may tolerate it, but plastics or softwoods may warp or splinter.
4. How do I know if a surface is safe to pressure wash?
Consult with professionals like KBC Services. We assess the material, condition, and setting before proceeding.
5. Can I pressure wash my home myself?
You can—but it comes with risks. Our article on DIY Pressure Washing Risks explains why expert help is often safer and more cost-effective.