Laser Stone & Brick Cleaning Machines UK

A laser stone cleaning machine removes soiling, black crust, biological growth, paint and graffiti from stone and brick by pulsing 1064nm light at the surface. Dark deposits absorb the pulse far more readily than the lighter stone beneath them, so the soiling lifts as vapour and fine particulate while the face of sound stone is left largely intact when the parameters are right.

That selectivity is the reason laser cleaning is discussed in conservation practice at all. Water and steam can drive salts and staining deeper into porous stone, abrasive blasting removes some of the face along with the dirt, and chemical cleaners leave residues that have to be neutralised. A dry, non-contact method avoids all three, which on a friable or historic facade can matter more than speed.

What comes off masonry well, and what does not

• Black crust and sulphation on sandstone and limestone, the classic urban soiling. See removing black crust from stone.
• Soot, traffic grime and atmospheric soiling on brick and stone frontages.
• Algae, lichen and biological growth, though some staining left behind by growth sits in the stone itself.
• Paint and graffiti on brick and stone. Aerosol lifts well; pigment soaked into open-pore stone can leave a shadow. See laser graffiti removal machines.
• Iron and rust staining is mineral staining within the stone, not a deposit on it, and a laser usually cannot remove it.
• Very pale or white stone can yellow slightly under some laser parameters. It is a known effect in conservation literature and a reason to work up from conservative settings on a discreet area.

Listed buildings, conservation areas and BS 8221

Cleaning a listed building can itself need listed building consent where it affects the building's character, and the decision rests with the local planning authority, not with the machine supplier or the operator. BS 8221-1:2012 is a code of practice for cleaning and surface repair of buildings; a documented, low-energy laser method can be aligned with it, which is what conservation officers generally ask to see. No machine is approved for listed work in itself. Our guides to cleaning listed buildings and cleaning sandstone without damage cover the method side in detail.

Stone types

• Sandstone and gritstone, including Yorkshire stone: the most common laser cleaning substrate in the north of England. See cleaning Yorkshire stone.
• Limestone: softer and more sensitive to over-cleaning. See the limestone cleaning guide.
• Marble: polished surfaces need particular care. See cleaning marble safely.
• Brick: soot, paint and graffiti off brick faces; the mortar joints behave differently from the brick. See removing paint from brick.
• Memorials and headstones, where a gentle, non-contact method is often the point. See cleaning a war memorial.

Which machine for stone and brick

For a business selling masonry cleaning as a service, the 500W is the machine we recommend: facades are priced by the job, so area cleared per day is the margin, and the 500W keeps the control that stone needs. The 300W suits occasional, detail-led work such as memorials, carved features and small frontages. Every machine is mobile and air-cooled, with a handheld cleaning gun, so it goes to the building rather than the building going anywhere.