How to pressure wash a patio

Spring

best time to pressure wash a patio in the UK to allow proper drying and prepare for summer use

30 to 45 degrees

correct angle to hold the lance when cleaning patio slabs to protect joints and prevent etching

Surface cleaner

attachment gives the best result on large patios, eliminating stripe patterns and covering area faster

Clear the area

Remove all furniture, plant pots and ornaments. Move them well clear so they are not hit by overspray or water running off the surface.

Sweep away loose debris

Sweep leaves, grit and loose dirt from the patio before starting. This prevents debris from being picked up and flung during washing.

Protect nearby plants

Wet adjacent plants and grass. Cover delicate plants with a tarp if using any cleaning solution to prevent overspray damage.

Check the surface for damage

Inspect for loose, cracked or subsiding slabs. Pressure washing worsens existing damage. Any structural issues should be repaired first.

Step 1: Initial wet pass on low pressure

Start on the lowest setting and pass over the entire patio to wet the surface and begin loosening dirt. This makes the main clean more effective and reveals how stubborn the soiling is.

Step 2: Apply cleaning solution if needed

For heavy algae or staining, apply a biodegradable patio cleaner and allow 10 to 15 minutes dwell time before washing. For lighter soiling, water pressure alone is usually sufficient.

Step 3: Main wash — work from one end, overlap passes

Start at one end and work across in overlapping sweeping passes. Hold the lance at 30 to 45 degrees to the surface and keep moving. Work diagonally to the joints rather than directly down them.

Step 4: Tackle edges and corners

Use a smaller nozzle or hand brush to clean edges, joints and any corners the main pass has not fully reached. These areas collect the most grime and benefit from additional attention.

Step 5: Final rinse

Complete with a thorough clean water rinse to remove all dirty water and cleaning product residue. Check for any missed areas and clean as needed.

Step 6: Re-sand block paving joints (if applicable)

If the patio is block paving, allow it to dry fully and then brush kiln-dried sand into the joints to restabilise the surface. This step is not optional.