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Best Patio & Driveway Cleaner UK: What Actually Works
10 July 2026 · 7 min read
An honest guide to the best patio and driveway cleaners you can buy in the UK — by stain type, surface and budget. No affiliate fluff.
Walk into any UK garden centre and you'll see a dozen bottles claiming to be the "best" patio cleaner. In reality, only a few chemistries do the real work. Here's what's inside them and when to reach for which.
The three chemistries that matter
- Benzalkonium chloride (BAC): the workhorse of moss/algae killers. Kills spores, prevents regrowth for 6–12 months, safe on most surfaces including resin. Sold as Patio Magic!, Wet & Forget, Algon (partly), etc.
- Sodium percarbonate ("oxy"): gentle bleaching action for tannin stains, general greying and black spot. Safe on natural stone. Sold as many "eco" patio cleaners.
- Sodium hypochlorite (bleach): fast and cheap. Great on concrete, awful on natural stone (bleaches it), can discolour resin.
What to avoid
- Brick acid / patio acid (hydrochloric): stripped-paint aggressive. Etches stone, weakens concrete, dissolves joint sand. Only use on specific mortar splashes — never as a general cleaner.
- Petrol-based solvents on tarmac: destroys the binder.
Best pick by scenario
| Problem | What to buy |
|---|---|
| Green algae, shaded patio | Any BAC-based "wet & forget" style spray |
| Black spot on sandstone | Sodium percarbonate ("oxy") patio cleaner |
| General concrete grime | Bleach-based patio cleaner (dilute) |
| Oil on block paving | Biological washing powder poultice + degreaser |
| Resin driveway | pH-neutral resin cleaner only |
Budget vs premium
Own-brand BAC concentrates from trade suppliers work identically to premium retail bottles — often at a quarter of the price. Look for the active-ingredient percentage on the label, not the marketing.