Thanks for your question.
I would try a two pronged approach. Contact the environmental health department and state that you have a damp situation and require an emergency inspection. They will send an officer round and either contact the landlord thereafter requesting emergency repairs, possibly by serving an enforcement notice which he will have to comply with (he will face a fine if he does not) OR they will in the worst cases of damp issue a declaration of uninhabitability. Either of these will quicken the landlord in dealing with it. I would play down the repair works he has tried, confirm that his attempts have ceased and that any previous repairs are inadequate. If they believe he is currently attempting repair works they will give him the opportunity of satisfactorily repairing them, but you want to keep the pressure on him.
You should formally write by registered post to the landlord (copying in the agent if any ) specifying the disrepair, making a list of the reasonable repair required and ask that he make those repairs within a reasonable time (eg. 14 days). Refer to earlier insufficient repaid works. State that if the landlord does not make the repair within that time you will pay to have the repairs made and will seek to claim the expense from him and are prepared to make an application to court if necessary.
If the landlord does not make the repair you can pay to have it done and then write formally to him requesting the payment of the cost, again within a reasonable time). If he does not pay you can issue a claim for the money yourself through Her Majesty Courts Service's online service: http://www.moneyclaim.gov.uk/. Write to them first asking for the money and stating that you will issue a claim if it is not received.
Its pretty cheap and straightforward to use.
Open a file, send letters by registered post, keep copies of everything for use in any claim you may choose to issue at a later date.
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