Render Cleaning Without the Damage
Green and black stains on your render? We soft wash K-rend, monocouche and silicone render – killing the algae at the root, with none of the damage high-pressure washing causes.
- No high pressure – zero risk to your render
- Stays clean for years, not months
- Fully insured & CHAS Premium accredited
- Free quote – same-day response
book my free site survey
Same-day response · No obligation
CHAS Premium
NEBOSH Diploma
Work-At-Height qualified
No Travel Surcharges
Professional Render Cleaning Across South Wales, the West Midlands & the South West
If you’re searching for render cleaning, your walls have probably turned green, streaky or black. That’s not dirt – it’s algae, mould and fungus feeding on the surface. It’s extremely common on modern renders like K-rend, monocouche and silicone, and it spreads further every year it’s left untreated.
The good news? It cleans off completely – if it’s done the right way.
Most cleaning companies will offer to jet wash it. Don’t let them. High pressure blows holes in modern render, forces water into the wall and leaves stripe marks that can’t be undone. We use soft washing instead: a low-pressure biocide spray, applied at garden-hose pressure, that kills the growth at its root. Your render comes back uniformly bright – and because the root is dead, it stays clean for years rather than months.
How Our Soft Wash Render Cleaning Works
1
Survey & fixed quote
Send us photos or we’ll visit free of charge.
No obligation, no hidden extras
2
Protect
We pre-water surrounding plants and protect windows, doors and paintwork before we start.
3
Treat
We apply our eco-friendly, biodegradable biocide at low pressure. No noise, no mess, no damage.
4
Transform
The treatment keeps working after we leave. Within 4–8 weeks your render is uniformly clean and bright.
Our biocides are biodegradable and break down into salt.
We simply ask you to keep pets off treated surfaces until dry – usually 2 to 4 hours.
Before and After
What we clean - Every Render Type, Homes and Businesses
- K-rend
- Monocouche
- Silicone render
- Painted render
- Roughcast and pebbledash
From single walls to whole houses, apartment blocks and commercial buildings
Why Homeowners Choose H2O
20+ years of exterior cleaning experience. Fully insured, CHAS Premium accredited, NEBOSH and IEMA certified. We’re local to Monmouthshire and cover South Wales, the West Midlands and the South West – with no travel surcharges.
Frequently asked questions
My render has gone green and black – can you clean it?
Yes. That discolouration is a combination of algae, mould and fungus – very common on K-rend, monocouche and silicone render. Our biocide spray kills it all at the root, and within 4 to 8 weeks your render will be uniformly bright again.
Will you pressure wash my render?
Never. High pressure blows holes in modern render and forces water into the wall. Soft washing at low pressure is the only safe method – it’s all we use on render.
How long will it stay clean?
Because soft washing kills the algae at its root rather than just blasting off the surface colour, results typically last years. Jet-washed render usually turns green again within months.
What does render cleaning cost?
Every property is different, so we price by the job – not by the postcode. Send photos and rough measurements through the form and we’ll give you a fixed, no-obligation quote, usually the same day.
Is the treatment safe for pets and plants?
Yes. We pre-water nearby plants and rinse thoroughly afterwards. Keep pets indoors until surfaces are dry – usually 2 to 4 hours – and it’s completely safe.
Get Your Render Cleaning Quote Today
Free, fixed and no-obligation – with a same-day response. Send us a couple of photos and we’ll do the rest.
