Shrewsbury's mix of block paving, Indian sandstone and old flagstones looks fantastic when it is clean, and grim when it is not. Two things spoil it: soft green moss and algae, and the stubborn dark spots people call black spot. They need different treatment, which is why a quick blast with a jet wash rarely gives a lasting result.
Moss and algae
The green film is a living growth that thrives in our damp climate, especially on shaded, north-facing paving. Pressure washing shifts the surface layer, but unless the spores are treated it comes straight back. We clean the paving properly and then treat it, so it stays clean for far longer.
Black spot is different
Those small dark, almost tar-like spots are lichen, and they bond hard to the stone. A domestic jet wash will not touch them, and blasting too hard can pit and scar soft sandstone. We use the correct treatment and controlled pressure to lift lichen without damaging the surface underneath.
The right method for the surface
Block paving gets a rotary clean and fresh kiln-dried sand brushed back into the joints so it locks together again. Natural stone and older flags get a gentler approach that protects the surface. You can see plenty of before-and-after transformations in our results gallery.
Full detail is on our driveway and patio cleaning page, we cover all of Shrewsbury and its villages, and you can get an instant price in seconds.