Red marks on through render walls.
I have a lot of inquiries for removing red marks from rendered walls. Most people have no idea what it is, how it got there and most importantly how to get rid of it! This blog post will hopefully answer some of the questions you may have…
What is it?
How is is to be cleaned?
Is pressure washing the answer?
Some people will choose to pressure wash the render to remove the red marks. This is a sure way to damage the walls. Through coloured render (common brands are: K Rend, Monocouche, Weber, etc. ) is a soft surface that need to be treated as such. We have seen some of the results from pressure washing through coloured render achieved by other cleaning companies and some of the results are terrible. Rather than killing the algae, using high pressure takes the top layer of the render away. As you can imaging, this is a bad way to clean this type of surface! This leaves etching on the through coloured render and damages the wall being ‘cleaned’.