A patio that becomes slippery in damp weather

Slippery Patio: Getting Rid of Algae and Green Film

That green film is algae, and it thrives where the surface stays damp — shaded corners, north-facing areas, and anywhere water sits rather than drains.

Cleaning it is straightforward. Keeping it away means dealing with the moisture.

Patio and Landscaping work by Gardenscape in Essex

Cleaning without damaging the paving

A patio cleaner suited to the material, left to dwell and then rinsed, is safer and more thorough than blasting. High-pressure washing erodes soft sandstone, opens joints and can etch concrete.

Never use acid-based cleaners on limestone or on jointing mortar.

Why it comes back so quickly

Shade, overhanging planting and poor falls all keep the surface wet. Cutting back planting to let air and light in makes a bigger difference than most cleaning products.

Where water ponds, the algae will always return first in those spots — that is a levels problem.

Longer-term options

Sealing reduces absorption so the surface dries faster, and some sealers include an anti-slip additive. Textured porcelain and riven stone hold grip better than smooth sawn finishes.

For a patio that is genuinely unsafe, re-laying with correct falls and a textured surface is the permanent answer.

Frequently asked questions

Is bleach safe on patio slabs?

It can discolour natural stone and damage planting in the runoff. A dedicated patio cleaner is safer.

How often should a patio be cleaned?

Most gardens benefit from one thorough clean a year, usually in spring or early autumn.

Does sealing stop algae completely?

No, but it reduces how much moisture the surface holds and makes cleaning much easier.

Patio unsafe underfoot?

We clean, seal and where needed re-lay patios with proper falls and grip.

Talk to us about your patio Call 07535 661664