Can Pressure Washing Damage Block Paving?
Alex Mcdonald7 October 2026 · 4 min readBlock paving can be cleaned safely. Damage almost always comes from the wrong pressure, the wrong nozzle distance or skipping the aftercare, not from cleaning itself.
Where damage usually comes from
Most problems I see come from holding a lance too close to the surface or blasting straight down the joints. That can wash out the kiln dried sand that locks the blocks together and leave the surface looking patchy.
- Too much pressure held close to the blocks
- Spraying directly into the joints
- Not refilling the joints afterwards
- Cleaning soft or already crumbling blocks without checking them first
How a safe clean works
I start by checking the condition of the blocks and joints. A rotary surface cleaner keeps the pressure even and at a fixed distance, which lifts dirt, moss and algae without gouging the surface.
Weeds and moss are cleared from the joints, the surface is rinsed, and the driveway is left to dry before any sand goes back in.
Why resanding matters
Fresh kiln dried sand brushed into the joints locks the blocks back together and makes it harder for weeds to take hold again. It's a big part of why a cleaned driveway stays looking good for longer.
Some older oil or rust stains may fade rather than disappear completely. I'll always tell you what to expect before I start.