1. What is K Rend ?

K Rend is a type of through-coloured external render used on the outside of buildings. It is manufactured by Kilwaughter Minerals and is widely used on modern homes and buildings in the UK and Ireland.

1. K Rend Cleaning Cost

Current UK pricing guides put professional render/softwash cleaning broadly around £5–£8 per m², with Checkatrade's August 2026 guide giving an average of £6.50/m². It gives typical totals of roughly £300–£600 for a terrace/semi and £600–£1,100 for a detached house.

1. How to Clean K Rend
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K Rend should be cleaned carefully because it is a textured external render, and using excessive pressure or unsuitable chemicals can damage the finish. The best & safest way to clean K Rend & other silicone renders is with Soft Washing with biocide.

Can K Rend Be Pressure Washed?

K Rend can be cleaned, but aggressive high-pressure washing is generally not the approach I would recommend for K Rend. The exact method should depend on the particular K Rend/render system, its condition and the type of contamination.

K Rend is a textured rendered finish, so excessive pressure can potentially:

• Damage or erode the surface texture
• Leave visible marks
• Dislodge material from weak or damaged areas
• Drive water into cracks or defects
• Produce an uneven-looking finish
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1. K Rend Algae Removal

K Rend algae removal is the process of treating and cleaning green algae and other organic growth from K Rend and similar external render finishes with softwash biocide treatment.

K Rend Black Stain Removal

Black staining is one of the most common reasons homeowners look for K Rend cleaning. It can make a relatively clean property look dirty and weathered, particularly on light-coloured render. Softwash biocide cleaning will remove black staining, but will take weeks or months to remove staining which has grown in to the render.

Why Does K Rend Go Green?

K Rend usually goes green because algae and other organic growth develop on the surface of the render. The green appearance is particularly common on walls that remain damp or receive limited direct sunlight.

K Rend Maintenance Guide

K Rend is designed to provide a durable, attractive external finish, but like any exterior surface it benefits from regular inspection and maintenance. Dirt, algae, mould, lichen and atmospheric pollution can gradually build up, particularly on shaded or damp elevations.

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2. K Rend Soft Washing
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Soft washing is a low-pressure cleaning method that uses specialist cleaning treatments to break down organic contamination on the surface of the render.

K Rend Cleaning FAQs

K Rend Cleaning Frequently Asked Questions

K Rend can become dirty, green, stained and weathered over time. Algae, mould, lichen, dirt, pollution and water run-off can all affect the appearance of external render.

Below are some of the most frequently asked questions about K Rend cleaning, soft washing and K Rend maintenance.

What is K Rend?

K Rend is a range of through-coloured and textured external render systems used on residential and commercial buildings.

Its textured surface can become contaminated with algae, mould, lichen, dirt and atmospheric pollution over time, particularly on shaded or damp elevations.

Can K Rend be cleaned?

Yes. K Rend can be cleaned, but the cleaning method needs to be appropriate for the particular render system and its condition.

A treatment-led soft-washing approach can be suitable for removing organic contamination such as algae, mould and lichen without relying on aggressive pressure.

How do you clean K Rend?

The exact process depends on the condition of the render and the type of contamination.

A typical professional cleaning process involves:

1. Inspecting the K Rend
2. Identifying the type of staining
3. Preparing surrounding areas
4. Applying an appropriate cleaning treatment
5. Allowing the treatment time to work
6. Carefully rinsing the surface
7. Inspecting the finished result

The aim is to remove contamination while minimising unnecessary mechanical pressure on the textured surface.

Can K Rend be pressure washed?

K Rend should not automatically be treated like concrete, paving or brickwork.

High or aggressive pressure can potentially damage or alter a textured render finish. In some circumstances controlled pressure may form part of the cleaning process, but the pressure and technique should be appropriate for the render.

For many organic stains, a soft-washing or treatment-led approach can reduce the need for aggressive pressure.

What is K Rend soft washing?

K Rend soft washing is a cleaning method that uses specialist treatment solutions to break down organic contamination, followed by controlled rinsing where appropriate.

It is particularly useful for problems such as green algae, mould, lichen and other organic staining.

Why has my K Rend gone green?

Green K Rend is commonly associated with algae and other organic growth.

Green staining is more likely to develop where walls are exposed to:

• Shade
• Persistent moisture
• Nearby trees and vegetation
• Poor water run-off
• Blocked or leaking gutters
• Damp conditions

North-facing and shaded elevations can be particularly susceptible.

Can green algae be removed from K Rend?

In many cases, yes.

A suitable cleaning treatment can help break down algae and other organic growth. The final result depends on how established the contamination is and whether an underlying moisture problem is contributing to the staining.

What causes black stains on K Rend?

Black staining can have several possible causes.

These may include:

• Organic growth
• Mould
• Atmospheric pollution
• Dirt accumulation
• Water run-off
• Contamination from nearby vegetation

Identifying the cause is important because different types of staining may require different cleaning approaches.

Can black stains be removed from K Rend?

Black staining can often be treated, but the result depends on its cause, severity and how long it has been present.

A professional assessment can help determine whether the staining is organic contamination, pollution, water run-off or another issue.

Will K Rend cleaning damage the colour?

K Rend is generally designed as a through-coloured render, but inappropriate cleaning methods can potentially affect the appearance of a textured render.

For this reason, cleaning should be carried out carefully, using an appropriate method for the specific surface.

Aggressive pressure should be avoided where it could damage or alter the finish.

How much does K Rend cleaning cost?

There is no single fixed price for K Rend cleaning.

The cost can depend on:

• Size of the property
• Amount of K Rend
• Height and accessibility
• Severity of staining
• Type of contamination
• Condition of the render
• Access requirements
• Amount of preparation required

A quotation or site assessment is therefore more useful than applying one price to every property.

How long does K Rend cleaning take?

The time required depends on the size and condition of the property.

A small area of lightly contaminated render may be relatively quick to clean, while a large property with extensive algae, black staining or difficult access can require considerably more time.

Soft washing may also involve treatment and dwell time rather than simply pressure washing the surface.

How often should K Rend be cleaned?

There is no universal cleaning schedule.

Some properties may remain relatively clean for several years, while shaded or damp properties can develop algae and staining much sooner.

Regular inspection is more useful than following a fixed timetable.

Keeping gutters clear, controlling vegetation and addressing sources of persistent moisture can also help reduce future contamination.

Can you clean K Rend that has gone very green?

Yes, heavily green K Rend can often be treated.

The cleaning process should be adapted to the level of organic growth. Where contamination is extensive, more than one treatment or cleaning stage may sometimes be required.

The underlying cause should also be considered to help reduce the likelihood of rapid regrowth.

Can you remove moss and lichen from K Rend?

Moss and lichen can be treated, although heavily established growth may require additional care.

The objective is to loosen and remove the contamination without unnecessarily damaging the textured render.

Can you clean K Rend around windows and doors?

Yes, but surrounding areas need to be taken into account during the cleaning process.

Windows, doors, seals, vents and other nearby surfaces may require appropriate protection and careful rinsing depending on the cleaning method being used.

Can K Rend be cleaned if it is damaged?

Damaged render requires additional care.

Cracks, loose areas, previous repairs or other defects should be identified before cleaning. Cleaning cannot repair damaged render, and aggressive cleaning may make existing problems worse.

Where significant damage is present, repair may need to be considered separately.

Does K Rend cleaning remove all staining?

Not necessarily.

The result depends on what has caused the staining and how deeply established it is.

Organic contamination can often respond well to appropriate treatment, while permanent discolouration, underlying defects or changes to the render itself may not be completely reversible through cleaning alone.

Can dirty K Rend be painted instead of cleaned?

Painting and cleaning are two different processes.

If K Rend is simply dirty or affected by algae, cleaning may be the appropriate first step. Painting should not automatically be used to cover contamination without addressing the underlying problem.

The condition and specification of the render should be assessed before considering any coating.

Does K Rend cleaning stop algae coming back?

Cleaning removes existing contamination but cannot guarantee that algae will never return.

Future growth can be influenced by shade, moisture, vegetation, drainage and the surrounding environment.

Good property maintenance can help reduce the conditions that encourage organic growth.

Should gutters be cleaned before K Rend cleaning?

Gutters and downpipes are worth checking as part of the assessment.

Overflowing or leaking gutters can repeatedly wet sections of render and contribute to staining. Cleaning the K Rend without addressing the source of the water may allow the problem to return.

Is K Rend cleaning suitable for houses?

Yes. K Rend cleaning is commonly required on residential properties where external render has become stained or contaminated.

The appropriate cleaning method depends on the render type, condition, accessibility and contamination.

Can you clean K Rend on a two-storey house?

Yes, but height and access need to be considered.

Two-storey properties may require additional equipment, access arrangements and safety precautions. The cleaning method should be planned around the building rather than simply applying the same process used on a small accessible wall.

Can you clean K Rend in winter?

K Rend can potentially be cleaned outside of the warmer months, but weather conditions are important.

Temperature, rainfall, wind and drying conditions can all affect the cleaning process. The work should be planned around suitable weather rather than carried out regardless of conditions.

Do you clean other types of render?

Yes. The appropriate method depends on the render system and its condition.

Mr Softwash can assess rendered surfaces and recommend a suitable cleaning approach rather than assuming every type of render should be cleaned in exactly the same way.

Where does Mr Softwash provide K Rend cleaning?

Mr Softwash provides K Rend cleaning and soft-washing services in Poole, Bournemouth, Christchurch, Wimborne, Ferndown and surrounding areas of Dorset, with services also available in Wiltshire, Hampshire and the New Forest.