Stone cleaning across the North East

Natural stone changes character as it weathers. Sandstone darkens, algae greens the shaded faces, black spots appear where lichen takes hold, and moss fills the joints of walls and paths. Left alone it does no structural harm in most cases, but it hides the colour of the stone and makes paths slippery.

Stone cleaning brings the surface back without eroding it. The method depends on the stone: soft washing, where a dilute solution at low pressure kills the growth, suits most sandstone and masonry, while low pressure steam helps where heat releases stubborn soiling. High pressure is used sparingly, if at all, because a hard jet scars soft stone and blasts out mortar.

This page covers walls, paths, steps and features in natural stone. For house walls in brick, see brick and stone cleaning; for rendered finishes, see render cleaning; and for the gentlest steam method on delicate or historic masonry, see DOFF steam cleaning.

Sandstone is one of the most common stones we are asked about, from boundary walls to Indian sandstone patios. It is porous and relatively soft, which is why it stains so readily and why aggressive washing is a mistake: the jet opens the surface and the stone gets dirty faster afterwards.

Indian sandstone paths and patios usually carry a mix of green algae, black lichen spots and general grime. A treatment kills the growth at the root, washing lifts the dirt, and the black spots fade as the killed lichen releases over the following weeks. Our guides how to clean stone walls and how to clean Indian sandstone go deeper into each.

We do not publish stone cleaning prices, because the job is set by the surface in front of us: the type and condition of the stone, the area involved, how heavy the growth is, access and water supply, and whether the stone can take any pressure at all or needs a slower, gentler approach. Tell us what you have, or send a photo, and the quote will reflect the real job.

Timing matters too. Stone cleans best in a dry spell, when treatments can dwell without being rinsed off by rain and surfaces dry evenly afterwards. Spring and autumn are popular, but the work can be done whenever the forecast allows a dry window.