Clean a patio — HomeGraft

Clear, treat and scrub a patio to lift dirt, moss and weeds, then rinse and let it dry before refilling the joints.

CP-01Clear the patioMove all furniture, pots and planters off the patio. Sweep away loose leaves, soil and debris with a stiff broom so you can see the whole surface and the joints between the slabs.

1 each · Stiff outdoor broom

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CP-02Clear weeds from the jointsPull weeds out by hand or use a weeding hook to get the roots out of the gaps between slabs. If growth is heavy, treat with a path and patio weedkiller instead and leave it for the time stated on the bottle, usually a few days, before you scrub.

1 each · Patio weeding knife

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1 bottle · Path & patio weedkiller

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CP-03Protect plants and bordersCover nearby plants, lawn edges and pond edges with plastic sheeting if you are using weedkiller, patio cleaner or moss killer close by, so run-off doesn't scorch them. Keep pets and children off the area while any chemical is working.

2 m · Plastic sheeting

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CP-04Apply patio cleaner and let it soakMix a concentrated patio cleaner with water following the bottle's instructions, or use a strong solution of washing-up liquid. Spread it over the whole area with a watering can or garden sprayer and leave it for 10-15 minutes to lift grime and break down algae before you scrub.

1 bottle · Patio cleaner concentrate

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1 each · Garden pump sprayer

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CP-05Scrub the slabsWork in manageable sections with a stiff-bristled broom, scrubbing along and across the slabs to get into the texture. Pay extra attention to shaded, damp corners where moss and algae build up.

CP-06Rinse the patioIf you're using a pressure washer outdoors, plug it into an RCD-protected outdoor socket, or fit a plug-in RCD adaptor if your socket isn't already protected, and keep the plug and lead connections clear of puddles. Hold the nozzle about 150-200mm from the surface, keep it moving, and work away from the house towards a drain so dirty water doesn't pool against the wall or door thresholds. A hose and stiff broom will do the same job more slowly if you don't have a pressure washer.

1 each · Pressure washer (or hire)

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1 each · Plug-in RCD adaptor

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1 each · Safety goggles

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CP-07Go easy on the jointsKeep the pressure washer jet at a slight angle rather than firing straight down into the joints. A close-up blast on old mortar or resin jointing can gouge it out, so lower the pressure or hold the nozzle further back over any joints that look worn.

CP-08Treat any stubborn moss or algaeIf green or black patches remain after washing, apply a dedicated moss and algae killer and leave it to work for the time stated on the label, often 24-48 hours, then rinse the area again.

1 bottle · Moss & algae killer

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CP-09Refill the jointsOnce the patio is completely dry, brush kiln-dried jointing sand or a jointing compound into the gaps between slabs. This firms up the surface and makes it harder for new weeds to take hold.

1 bag · Kiln-dried jointing sand

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1 each · Stiff hand brush

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CP-10Let it dry and put everything backLeave the patio to dry fully, ideally overnight, before walking on it again or putting furniture and pots back. Wet slabs are slippery, so keep pets and children off until they're dry.

CP-11Clean up and store chemicals safelyRinse out the sprayer, broom and any buckets. Store leftover weedkiller, moss killer and patio cleaner out of reach of children and pets, and don't pour chemical run-off or leftover concentrate down a surface water drain, into a pond, or onto open ground near a watercourse.

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