We are currently renovating and extending a Grade II Listed, 17th century stone rubble cottage. The property has no damp proof course and we are in the process of raking out 1970s concrete-based pointing to replace with lime. Internally there was significant evidence of damp such that we have stripped out the concrete ‘plastering’. The property has a solid concrete floor that does not appear to have any damp proofing and is not insulated.
We have received advice at both ends of the spectrum regarding how to take the renovation forwards – do we tank internally whilst allowing the walls to breathe out through the lime pointing, or do we use lime plaster internally and allow the walls to breathe in both directions?
In addition, how should we manage the floor and wall/floor interface – do we seal it with a damp membrane up to above the skirting or cut it away from the walls to allow a breathing space around the room?
The walls appear to be drying out well now the concrete facing has been removed but if we follow the full lime solution I fear mouldy walls behind furniture and a damp cold floor.