Render Cleaning Belfast

Diamond Property Maintenance NI soft washes rendered walls across Belfast and Northern Ireland, treating K-rend, monocouche, silicone and traditional renders without the pressure that damages the surface. Modern render finishes are porous and easily marked, so we never blast them clean. Instead we use a low-pressure soft wash and a biocide treatment that kills the growth at the root and keeps the wall clean for far longer than a pressure wash ever could.

Why does render go red, green or black? The pink or red staining that spreads across so many rendered homes in Northern Ireland is algae, and it thrives in our damp, mild climate. Green algae and black mould take hold in the same conditions, and general pollution and traffic grime add a grey film on top. Because render is textured and porous, this growth roots into the surface rather than sitting on top of it, which is why simply hosing it off never works.

Our process starts with a gentle soft wash to lift the surface dirt, followed by a biocide treatment applied across the whole elevation. The biocide keeps working after we leave, killing the algae spores at the root so the render stays clean rather than greening straight back over. We deliberately avoid high pressure because it erodes the render, opens up the surface and can force water behind it.

Will pressure washing damage my render? Yes, which is exactly why we do not use it. High-pressure cleaning strips the coloured coating, pits the surface and shortens the life of the render. Soft washing achieves a better and longer-lasting result without that harm.

How long does render cleaning take? Most homes take one to two days including the biocide treatment, and taller or more complex properties sometimes need scaffolding for safe access. Pricing works out around £3 to £5 per square metre. Every job is carried out by our PASMA and IPAF certified team, backed by 30 plus years of experience and £10M public liability cover.