Service

Roughcast Render Cleaning

Roughcast Render Cleaning and Care

Coloured through Roughcast is a type of render system with the colour all the way through it, Usually this is made up of an Acrylic or silicone based coating and an aggregate grain to give an attractive finish.

The fact the colour is all the way through means painting is usually not necessary. However it does need some cleaning and maintenance periodically to keep it looking great.

Why Does my Roughcast Render look dirty?

The discolouration that appears on render can be green, black and sometimes red. This discolouration is biological growth and possibly some general dirt, grime and traffic film from general pollution. Algae manifests as green and red Staining whereas black Staining is usually fungus growth. All of these stains can usually be cleaned away leaving the property walls looking like new.

How can I clean my Render?

The procedure for cleaning and ongoing maintenance for roughcast rendered walls is very similar to that for cleaning silicone based scratch finish render. Appropriate chemical cleaning and low pressure, medium temperature Cleaning is very effective for Roughcast Render, along with biocide treatments. This is sometimes referred to as Softwashing.

Softwashing has the advantage of being a gentle way of cleaning when it is done correctly as it will not cause any unnecessary erosion to the surface unlike careless use of a pressure washer or using inappropriate nozzles such as rotating turbo nozzles. The other advantage of Softwashing or cleaning with an appropriate broad spectrum chemical is that it will destroy any biological growths and active spores on the surface, meaning that the surface will stay cleaner for longer.

The surface finish of Roughcast is generally much less Porous than the scratch finish types of render. This means a slightly different approach can often be taken with the cleaning process and slightly longer times between maintenance treatments is possible. The deep grain of Roughcast can make it more difficult to clean if it is very dirty and usually a number of methods are required to get it looking like new.

It is also important to clean and treat all adjacent surfaces such as gutters, UPVC, reveals and plinths, we always do this when cleaning render to help you get the best longevity and value for your money.

How to paint Roughcast Render

This type of coloured Roughcast finish looks very similar to a painted finish, but it’s important that it is not painted when it becomes dirty as this is a very costly and unnecessary step when it may simply need cleaning. Usually the surface has a life of 25-30 years before any repairs are needed. However if the render is very old and weathered, so much that the aggregate is showing, it may be a good option to re-coat the render. A vital step before painting is to properly clean and stabilise the surface.