Stone Patio Cleaning and
Gutter Cleaning in
Marlow, Buckinghamshire

A relatively new natural stone patio that had already developed heavy moss, green algae and the early signs of black spot — cleaned carefully, and protected against rapid regrowth.

The project at a glance

A newer patio
already deteriorating

Free site assessment and diagnosis

Every Chiltern Surface Co project starts with a free site assessment of the surface and its environment, so we understand exactly what the property needs and can provide an accurate quotation.

On this Marlow patio we inspected the paving, slab edges, joints and surrounding features before choosing the cleaning method. We confirmed extensive moss and algae, general organic build‑up and early black spot.

Black spot is not simply surface contamination. It lives inside the stone itself, so surface cleaning alone is not enough. In fact, pressure washing black spot off a surface drives oxygen and fresh water deep into the pores of the material. The immediate effect is a cleaner‑looking surface, but what has actually happened is that the black spot has been fed the water and oxygen it needs to return stronger and thrive.

That is why the Chiltern EverGuard™ treatment is a crucial element of the work.

Professional pre‑treatment and controlled stone patio cleaning

The complete patio received a professional surface pre‑treatment before mechanical cleaning began. The treatment was given appropriate dwell time to start breaking down moss, algae and other biological contamination. This stage helps loosen organic growth before mechanical cleaning and reduces the need to rely on unnecessarily aggressive pressure.

That was particularly important here because the paving was comparatively new. The aim was to remove the contamination while preserving the surface and surrounding jointing.

Once the treatment had worked, we cleaned the approximately 28m² patio methodically using professional surface‑cleaning equipment. The pressure and working distance were controlled throughout. More attention was given to slab edges and the areas carrying heavier contamination, including the developing black spot.

As the moss, algae and dirt were removed, the natural variation and texture of the paving became visible again. The improvement was not simply a change in brightness; the stone recovered much more of the character that had been obscured by the biological growth.

Chiltern EverGuard™ surface protection

Cleaning removed the established contamination, but the homeowner’s original concern was how quickly the patio had deteriorated. Surface cleaning alone is not enough: it removes what is visible, while the growth living inside the pores of the stone survives to return.

That is why the protective stage was central to this project. After cleaning, Chiltern EverGuard™ was applied across the complete patio. It penetrates into the pores of the material, killing the growth living inside the stone and inhibiting regrowth of moss, algae, lichen and black spot.

Chiltern EverGuard™ inhibits regrowth, typically for two to three years, depending on the surface and its environment. Residual organic staining can also continue to break down in the weeks and months after treatment.

For this property, that meant the finished job addressed both the immediate appearance of the paving and the homeowner’s concern about rapid regrowth.

The completed patio clean

A return visit
for the gutters

The client was extremely pleased with the result. They subsequently commissioned Chiltern Surface Co to return and carry out a full gutter clean to both the main house and a separate outbuilding.

Chiltern Surface Co provides gutter clearing and cleaning across Buckinghamshire, Oxfordshire, Berkshire, Hertfordshire and Surrey.

Stone Patio Cleaning in Marlow, Buckinghamshire