Just to add I have now removed a board to investigate, subfloor is bone dry. Smell seems to be coming from the wall itself, possibly from the basement which could have a bit of damp behind the tanking membrane. I've removed a chunk of insulation around pipework to improve airflow and going to...
Have just moved into a new property, it's an early Victorian townhouse with a fully converted and tanked basement. Typical terrace layout with lounge at the front, dining room behind lounge and the kitchen behind the hallway offset to the side.
It was mentioned in the survey about a lack of...