Stone Cleaning: What It Costs, and When It's Worth Doing

Straight answer: the cost of cleaning stone depends on the method the stone needs, how much there is to remove, and access — but the first honest question is whether cleaning is the right call at all.

Stone is easy to clean badly. Too much pressure or the wrong chemical strips the weathered surface and opens the stone up to faster decay — and you can’t put that back. So before we talk cost, it’s worth talking about whether.

First: is cleaning the right call?

Sometimes it isn’t, and a good mason will tell you so.

• Weathering can be character. On an older building, an even patina is part of how it should look — and removing it can make the stone look wrong and weather faster.
• Staining is often a symptom. Green growth and damp streaks usually come from a pointing or water problem — a failed gutter, a hard cement joint trapping moisture. Clean it and it comes back; fix the cause and it often doesn’t.
• Soft or friable stone may not take cleaning at all without losing surface.

If cleaning is worth doing, the next thing that sets the price is the method.

The methods (and why they cost differently)

There’s no single “stone clean” — the method is matched to the stone and the soiling, after a test:

• Gentle, low-pressure washing for general grime and light biological growth.
• Superheated-water systems (low pressure, high temperature) to lift paint, limewash and stubborn biological growth off stone without harsh abrasion.
• Poulticing to draw out specific stains.
• What we don’t do: dry grit or high-pressure sandblasting on historic stone. It’s quick and cheap, and it removes the weathered “case” of the stone — which is exactly the harm you’re trying to avoid.

Gentler, more selective methods take more skill and time, which is part of why a proper clean isn’t the cheapest number you’ll be quoted.

The cost drivers

• Method required — a light wash, paint removal, and stain poulticing are very different jobs.
• Area and access — a single feature versus a full elevation needing scaffold.
• How much there is — light grime versus several coats of old masonry paint.
• Stone sensitivity — soft or decayed stone has to be worked more gently and slowly.
• Test panel, protection and water management — done properly, these are part of the job.

”Ballpark”, honestly

Cleaning is priced after a test patch, because the method — and therefore the rate — only becomes clear once we see how the stone responds. A per-square-metre figure given without a test, on the right method, is an estimate at best.

How to compare quotes fairly

Ask each contractor:

• What method, and why that one for this stone?
• Is a test patch included before committing to the whole elevation?
• What exactly is being removed — grime, paint, biological growth?
• How is the surrounding area protected and the water managed?
• What’s excluded?

If a quote leads with high pressure or blasting on old stone, be wary.

How we approach it

We test first, use the gentlest method that actually works, and we’ll tell you honestly when the weathering is better left than cleaned. The test is simple: the dirt comes off, the stone doesn’t.

Get a reliable quote faster: what to send us

Send a wide photo of the whole elevation, a close-up of what you’re trying to remove, a note of whether it’s grime, paint or growth, whether the property is listed, and your postcode.

Send it over and we’ll give you an honest steer on whether — and how — it’s worth cleaning.