civetcat
The council's environmental health dept can serve a notice on the landlord to deal with the mould (I used to work in this area). Be specific it's about the mould, say that floors are coming up and mention any vulnerabilities (eg disability and health conditions, especially respiratory ones, which can be exacerbated by mould). If the environmental health aren't helping, they should contact the local councillor
I was going to suggest this. A former neighbour rented a property and it was really damp. Clothes in the cupboard had mould on them, as did shoes.
She got the council to come out (even though it was a private rental) and they made the landlady treat the mould and provide a dehumidifier.
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