Does your K-Rend look dirty? Nature is why your render looks dirty. Your render is exposed to nature and all the life around it, providing the perfect home to some of that life. Below we discuss what K-Rend is and what those stains are.
What is K-rend?
K-rend is a limestone and mineral-based coloured wall coating. It is a brand name owned by Kilwaughter Minerals Ltd., Coming in over 500 different colours. It is usually applied in a thick coat either by hand or machine. It is pre-coloured throughout, making it unnecessary to paint.
How can K-rend appearance change over the years?
K-Rend is a very porous material. Algae, lichen and black mould can easily find a home on the porous surface. Usually, one or two sides of the building will be more affected than the rest. This is because algae, lichen and black mould grow very well in damp and murky conditions. They will usually show first on the side of the building that faces prevailing winds away from regular sunlight.
Early growth will look green in colour and is the easiest to treat. However, left to mature, the rendered surface will show red streaks, almost like the building is bleeding. This is more difficult to treat but can be done by an expert using the correct pressure and chemicals.
The later stages of growth can include black marks, usually black mould. Again, this is relatively easy to treat by a professional with the knowledge and expertise in steam cleaning, biocide selection and appropriate application.
Why does this staining frequently appear on render?
K-Rend is a very porous material, allowing the wall to remain wet for longer after periods of rain. In addition, modern insulation is very efficient. This insulation will enable walls to stay moist for longer as there is little to no heat exiting cavity walls, keeping the heat inside. Most staining on rendered surfaces is algae.
Both green marks and red streaks come from algae colonies growing on the surface. They thrive in damp conditions with relatively low sunlight, which is why the algae growth is usually only on some sides of the building. Usually, the conditions are only suitable on one to two sides.
Can it be cleaned, or do I need to paint my render?
Your render can be cleaned. We can almost always remove the red streaks and all other stainings and return your render to its intended condition. It is a delicate process, and a high-powered pressure washer will almost certainly damage the soft and porous render.
Experience and knowledge are both required in selecting the correct chemical. For example, weather and temperature can adversely affect the efficiency of the chemicals.
Call or email us today to discuss returning your render to its finest condition.