Green growth or dirt build-up on resin bound surfacing

Moss, Algae and Grime on a Resin Driveway: Cleaning It Without Damage

Resin bound surfacing does not grow moss out of itself. Moss and algae live in the thin layer of organic silt that settles into the open texture of the stone, so a mossy resin drive is really a dirty resin drive that has not been cleaned for a while.

That matters because the answer is different from the answer for slabs. Resin is a bonded surface with voids running through it, and the wrong cleaning method drives dirt deeper, blocks the drainage or strips stone out of the matrix.

Resin-bound Surfacing work by Gardenscape in Essex

Why it takes hold, and where first

Look at where the green is and you will usually find the cause. North facing sections, the strip under a hedge, the shaded side of a house and anywhere leaves gather all hold moisture for longer, and that is exactly where growth appears while the sunny half of the drive stays clean.

The second factor is organic debris. Leaf fall, blossom, grass clippings blown over from mowing and soil washed off a border all break down into a fine film that sits in the surface texture and gives spores something to root into.

A drive that never dries out is the third factor. Resin bound is permeable by design, so if water is now sitting on the surface rather than draining through, the voids have silted up and the growth is a symptom of that blockage rather than the cause of it.

Cleaning it safely yourself

Start dry. Stiff brush the surface and clear all loose debris, because washing debris into an open textured surface makes matters worse. Pay attention to edges and any low points where silt collects.

Then use a proper moss and algae treatment suitable for resin bound surfaces, applied to a dry surface and left to work for the time the label states rather than rinsed off straight away. Most work over days, not minutes, and the growth turns brown and brushes off.

If you use a pressure washer, keep it at a moderate pressure, use a wide fan nozzle rather than a pencil jet, hold it well back and keep it moving at a shallow angle. A concentrated jet held close will strip stone out of the resin and leave a permanent bald patch, which is the single most common way homeowners damage a resin drive.

Avoid strong acids, neat bleach and salt. They can discolour the aggregate and shorten the life of the binder, and salt run-off does no favours to planting alongside.

When it is not just dirt

If water pools on the surface after cleaning, the voids are blocked further down and normal washing will not restore them. That usually happens where soil has repeatedly washed across the drive, and it needs the source dealt with as well as the surface cleared.

If cleaning reveals loose stone, exposed patches or cracking, you are looking at a laying or base issue rather than a cleaning one. Resin that is releasing stone across an area was either laid with the wrong ratio, laid in unsuitable conditions or is moving over a failing base.

We inspect, clean and where necessary repair resin bound surfacing, and any new resin work we lay is covered by our ten year guarantee.

Frequently asked questions

Can I jet wash a resin bound driveway?

Yes, but carefully. Use a wide fan nozzle at moderate pressure, keep the lance well back and keep moving. A close pencil jet will blast aggregate out of the resin and the bald patch it leaves is permanent.

How often should a resin drive be cleaned?

A brush down every few weeks and a proper wash once or twice a year suits most drives. Shaded or tree lined drives benefit from more frequent clearing of leaf fall.

Will moss damage the resin itself?

The growth itself does not attack the binder, but the damp organic layer it lives in holds water against the surface and blocks drainage, which is what shortens the life of the drive.

Is bleach safe on resin bound surfacing?

We would not use it. Neat bleach and strong acids risk discolouring the aggregate and degrading the binder, and there are moss treatments made for the job that do not carry that risk.

Water sits on my resin drive now. Is that normal?

No. Resin bound should drain through. Standing water means the voids have silted up, usually from soil washing across the surface, and it needs clearing properly rather than just cleaning the top.

Resin drive looking green and tired?

We clean, repair and lay resin bound surfacing across Essex. Send a photo for honest advice.

Ask about resin cleaning Call 07535 661664