Green, slippery decking is a safety hazard — and a waste of a good outdoor space. We clean timber and composite decking safely, restoring the surface and making it usable again. Free quotes, fully insured.
Decking is one of the most prone surfaces to algae and green mould — the texture and grain of timber in particular provides a perfect environment for growth. Within a season, a newly laid deck can become slippery enough to be genuinely dangerous. Composite decking isn't immune either, developing green staining and biofilm on its surface.
Decking requires careful cleaning — too much pressure on timber can raise the grain, splinter the surface or force water deep into the wood. We use appropriate lower pressure with the correct fan nozzle, always working along the grain of the timber, not across it.
After cleaning we can apply a biocide treatment to inhibit regrowth, and arrange oiling or staining for timber decks to protect the wood and restore colour. We'll advise on the best approach for your specific deck at the quotation stage.
Get a Free Decking QuoteWe identify your deck material, note any damaged boards or loose fixings, and set the right pressure and technique — critical to avoid raising the grain on timber.
Garden furniture, planters and any obstacles moved aside so we can clean the full deck area properly.
Heavy algae and stubborn staining treated first to loosen the biofilm before pressure washing begins.
Low-to-medium pressure applied in the direction of the grain. Steps, balustrades and edges all cleaned as part of the same process.
Biocide applied if agreed. Furniture replaced. We advise on oiling or staining once dry, and how to maintain the deck going forward.
It can — if done incorrectly. Too much pressure, the wrong nozzle or cleaning across the grain rather than along it can raise the grain, cause splintering or force water deep into the wood. We always use appropriate lower pressure and work along the grain. This is one of the key reasons to use a professional rather than a hired machine on maximum power.
For timber decking, oiling after cleaning is highly recommended. A good deck oil penetrates the wood, protects against moisture and UV damage, inhibits mould regrowth and restores colour. The deck needs to be dry before oiling — typically 48–72 hours after cleaning in good weather. We can arrange oiling as a follow-up visit or advise on DIY products.
Composite decking is generally more tolerant of pressure washing than softwood timber, but it still benefits from a careful approach with appropriate cleaner. Some composite manufacturers have specific cleaning recommendations, and we take these into account. The result on composite is excellent — green staining and biofilm come away very effectively.
Annually is ideal for timber decking, especially in Lincolnshire's damp climate. Composite decking may only need cleaning every 1–2 years. Regular cleaning prevents algae from becoming deeply ingrained and keeps the surface safe throughout the year.
Cleaning is worthwhile even with some damaged boards — in fact, cleaning first lets you see exactly which boards need replacing, since soiling can disguise the extent of damage. We'll flag any boards that look structurally compromised during the assessment, so you have a clear picture of what the deck needs.