The previous owner of our house used to have raised beds in the garden up against the outside wall of the house. In order to prevent damp seeping through the wall into the living room, he painted black waterproof paint on the exterior wall.
I've removed these beds as I'm landscaping the garden however I'm now left with ugly big black patches all over the outside wall. Does anyone have any advice for removing the paint? Conventional paint strippers don't touch it!