I have a large limestone block retaining wall out the side of our house, and I'm wondering if anyone can tell me what the white powdery substance is that seems to come about on it??
I have hosed it off a few times and it just seems to come back, and it also appears to kinda eat into the wall a little bit. I've noticed this at a previous house that we had but it was nowhere near as bad. It looks terrible and i'm wondering if it could be caused by acidity from rain eating into the limestone ...or something similar??
When you touch it with your finger etc it looks like you've dipped your finger in talcom powder or similar.
Is there a way to stop it/get rid of it?? .. like a spray on wash or something to neutralise it?
I just can't stand the look of it anymore.
Thanks in advance! (I hope someone knows what i'm talking about lol)