Render Softwashing
Safe, low-pressure biocide cleaning for K Rend, monocouche, pebbledash and painted render systems. The only cleaning method approved for modern through-coloured render. From £400.
Why render needs specialist cleaning
Modern render systems — K Rend, Weber, monocouche, through-coloured scraped finishes — are designed to be durable and low-maintenance. But they are not self-cleaning. Algae and green mould colonise the textured surface within 3–8 years depending on aspect, and once established, the growth is deeply embedded in the render's texture.
The critical point: pressure washing damages render. High pressure strips the surface layer, opens the texture, and creates micro-cracking that accelerates future biological colonisation. K Rend's own technical guidance explicitly states that pressure washing voids the product warranty. Softwashing — low pressure biocide application — is the only cleaning method approved by major render manufacturers.
Render types we clean
- K Rend and K Rend Silicone systems
- Weber one.coat monocouche render
- Sto render systems
- Traditional sand-and-cement render (painted or unpainted)
- Pebbledash and tyrolean finish
- Lime render (heritage properties)
- Dash and roughcast
What's included
- Pre-job survey to identify render type and condition
- Low-pressure biocide application to all affected elevations
- Window and door protection where required
- Rinse and inspection
- Before/after photo report
- 5-year regrowth protection guarantee on the treatment
Pricing
| Property type | From |
|---|---|
| Semi-detached | £400 |
| Detached | £550 |
| Large / extended | £800+ |
| Commercial facade | POA |
Price depends on elevation area, render type and degree of colonisation. Bundled discount available when combined with roof softwash.
Frequently asked questions
Why can't I just pressure wash my render?
Pressure washing penetrates the surface layer of modern render systems, strips texture, and opens micro-cracks that allow water ingress and accelerate future biological growth. K Rend's technical guidance explicitly warns against pressure washing and states it voids the product warranty. Softwashing achieves a better result — cleaner for longer — without any surface damage.
Is the biocide safe on coloured render?
Yes. We use biocide formulations tested on all major render systems including K Rend, Weber and Sto. The biocide does not affect pigment, texture or water repellency — it simply kills the biological growth on the surface. We always test on a small inconspicuous area first if there is any uncertainty about a specific render system.
How long does render softwashing last?
Typically 3–5 years, depending on aspect and local conditions. South and west-facing elevations in sheltered, damp environments may see algae return in 3 years; north-facing elevations in less humid areas often stay clean for 5+ years.
Can you clean both the roof and render in one visit?
Yes — and this is the most cost-effective approach. Combining a roof softwash and render softwash in a single visit saves on mobilisation costs and gives a discount on the render price.
Do you clean lime render on heritage properties?
Yes, with care. Lime render requires a lower-concentration biocide than cement-based systems. We always survey lime render properties before quoting and can provide method statements for listed buildings or planning authority requirements.
Get a free render softwashing quote
Most quotes returned within 4 working hours. No pressure, no obligation.
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