What is the best treatment for "salt damp" caused by hygroscopic salts on a chimney breast?
First, hack out the affected area of plaster and a good margin around it, and check the water isn't coming in through the bricks. I'm only talking about the case when water isn't still coming in.
But then?
Is it better to use a bond coat of SBR and then a cement render, perhaps itself with a splash of SBR in it, and then plaster or emulsion on top? I thought SBR wasn't breathable.
Or is it better to use a special "renovating plaster" that is sold precisely as breathable?
I don't quite get whether you want breathability or the opposite.
Advice would be welcomed.
Thanks in advance!
Harry