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Render cleaning advice
Can You Pressure Wash Render?
Sometimes, but it is not our default. Here is why most render is better cleaned with a low-pressure softwash.
- Low-pressure softwash, not a jet wash
- Method chosen to suit your render
- Quotes from photos
BeforeAfterThe short answer
Why You Should Think Twice Before Jet Washing Render
Lots of homeowners assume a pressure washer is the quickest way to clean a green wall. It can be tempting, but render is not like a patio. It is a finish that protects your walls, and many render systems are not designed to take hard pressure.
So the honest answer is: sometimes, in limited circumstances, but it is not our default. Whether any pressure is suitable depends on the render type and its condition, which is why we assess before we clean. In most cases we use a low-pressure softwash instead.
What Can Go Wrong With High Pressure on Render
Used on the wrong render, or at the wrong pressure, jet washing can:
- Mark, crack or blow small holes in the render
- Strip paint and protective coatings
- Force water behind the render, around windows and into cracks
- Leave a patchy, uneven finish
- Loosen weak or poorly bonded areas
These risks are higher on older, painted, weathered or already cracked render. Water forced behind a finish can contribute to damp and trapped moisture, and none of that is what you want from a clean.
What We Do Instead
Softwashing is a low-pressure method. Here is how a render job runs.
1Look at the render first
Render type, condition, cracks, how much growth there is and what is nearby all decide the method.
2Treat at low pressure
A softwash treatment is applied and left to work into the surface, rather than blasting the dirt off with force.
3Rinse gently and check
The treatment is rinsed off gently and we check the finished wall and the area around it.
Which Render Can Be Softwashed?
We clean K-Rend, monocouche, silicone render, pebbledash and painted render. They all behave differently, so we identify what we are dealing with before we agree an approach. Painted render needs particular care, because the paint layer has to be protected as well.
Signs your render needs cleaning
- Green staining
- Black spotting
- Red algae
- White lichen marks
- Dirty weather streaking
- Patchy discolouration, often on shaded walls
These are very common on UK homes, especially on shaded walls, near trees and where the wall stays damp. We do not diagnose from a blurry photo: some marks are growth and some are age or damage, so we look first.
Will the Green Come Back?
Algae can return, because a damp, shaded wall will always tend to grow it. How soon depends on trees, shade, which way the wall faces and how exposed it is. We will not promise it will never come back, but we will tell you honestly what we expect for your house.
Cleaning is also not repair. It will not fix cracks, failed coatings or damp, and it will not promise the exact original colour back. If we see a render problem that needs a different fix, we will tell you.
Render Cleaning Questions
Can you pressure wash render?
Sometimes, in limited circumstances, but it is not our default. High pressure can be too much for many render systems, especially older, cracked, painted or weathered finishes. We assess the render first, and in most cases we use a low-pressure softwash method instead.
Will jet washing damage my render?
It can. High pressure can crack or mark render, strip paint or coatings and force water behind the finish. Whether it will on your wall depends on the render type and its condition, which is why we look before we choose a method.
What is softwashing?
A low-pressure cleaning method. A treatment is applied to the render, left to work into the surface, then rinsed off gently. It relies on the treatment rather than force.
Is the staining definitely algae?
Not always, so we do not guess from an unclear photo. Green, black, red and white marks can have different causes, and some marks are damage or age rather than growth. We assess it before we quote.
Will the green come back?
Algae can return, because render that stays damp and shaded will always tend to grow it. How soon depends on shade, trees, which way the wall faces and how exposed it is. We will talk through what to expect for your house when we quote.
Can you clean painted render?
Yes, but painted render needs a gentler approach, because the paint layer has to be protected as well as the render underneath. We assess it first and choose the method to suit.
Get Your Render Assessed
Send us your address and a few photos, and we will tell you what we would do and give you an honest quote.
Local. Reliable. Professional.
Or call 07835 005 004 · Mon–Fri 7am–8pm, Sat 8am–12pm
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