I purchased a house (London clay) that has damp in most of the lower ground floor walks - external walls and also lower part of the internal walls incl. in the hallway. Hallway has wood floor that is damaged. So, I'm putting new wood floors glued on top of it. The surface below wood is concrete floor, battens and the current wooden planks on it, on which I'll put the new ones. As in the photo. Surveyor said that this void needs to be ventilated. He said airbricks externally, sleeved into the wall into the sub-floor void, installed every 3 metres or so and should roughly align with the internal floor void level. I'm not sure how that could be done and nor is the builder. Any ideas on how to ventilated this void?
