Deck and patio cleaning sets up the surface for sealing and protects the investment in the structure beneath it.
01Wood deck
Sweep debris before wetting the surface — wet debris is harder to move and leaves stains. Apply a deck cleaner or brightener appropriate for the wood species — a pH-neutral cleaner for new or recently finished wood, a brightening cleaner (often containing oxalic acid) for weathered gray wood. Apply with a garden sprayer, let dwell per the instructions, then scrub with a stiff brush and rinse thoroughly. Let the deck dry a full week before applying any sealer or stain.
02Composite deck
Composite decking cleans with soap, water, and a soft-bristle brush — the same approach as washing a car. Avoid pressure washers on composite decking; the high pressure can raise the grain of the material and damage the cap stock on capped composite boards. For mold and mildew on composite, a diluted oxygen bleach solution is effective and safe for the material.
03Concrete patio
Pressure wash with a surface cleaner attachment — the spinning head covers more area than a single wand and produces more even results. For persistent algae or mildew staining, apply a concrete cleaner with sodium hypochlorite, let it dwell, scrub, and rinse. For rust stains from metal furniture, a commercial rust remover for concrete or oxalic acid solution removes the staining.
04Paver patio
Sweep debris, apply a paver cleaner, scrub with a stiff brush, and rinse. After cleaning and drying, check all joints for weed growth and joint sand displacement. Pull any weeds, add polymeric sand to joints that have opened, and compact. If the pavers are heavily stained from algae or tannin from leaves, a dedicated paver brightener restores the original color.
Marcus Webb is a general contractor and home maintenance writer based in Columbus, Ohio. He writes about the repairs and installs that come up every year in every house — the practical, repeating work that keeps a home livable.