If the mould is as bad as you say then the deposit scheme will probably want to know why you didnt pick up on the issue and intervene sooner and why you think its caused by the tenants lifestyle and not damp ingress.
Hi Kay4
I’d be careful of getting a builder in to ‘fix’ the issue. We did the same in the summer and as they are not damp experts, they unwittingly did not fix it but made the issue worse. I would strongly recommend getting a damp surveyor to identify the causes and go from there, otherwise you’re just putting a sticking plaster on what can be a huge issue
so right A previous stone house I lived in had no dampcourse and had no damp problems tho 200 years old , I insulated all the external walls inside each room . . When I later moved home pulled the wardrobe away from the wall there was a trace of mould on the wall. because of No air circulation behind it. We never dried clothes in the home . had a vented out tumble drier. Fans in the utility and bathroom , Extractor in the kitchen , never a problem. My property s are well insulated , no probs. I have seen jobs I have worked on as a builder where leaks have caused the mould , and bad habits by the home ownner has caused mould