Hi there, would be grateful for some advice on this. I need to patch from bare brick as you can see in photo and want to know what the best undercoat is. It’s an old cottage and it’s solid wall so chance of damp even just small amount. The bonding that came off practically fell of so clearly wasn’t adhering to the wall. Is SBR then sand and cement a good option for this case? Can give more details. Thanks a lot