I am the owner occupier of a converted leasehold Ground Floor Flat. The only other flat in the building on the first floor is currently let by the owner (and the freeholder of the property). For the last two years my life has been disrupted to such an extent by four different sets of tenants that it has now become totally untenable. The current tenants have been in residence for almost 4 months and from the first day they have behaved in my opinion in a totally unacceptable manner. They play their music extremely loud at all times but particularly into the early hours of the morning, shout, scream etc and on a number of occasions seem to be playing football in their hallway. They are always holding parties with at least a dozen people running backwards and forwards generally adding to noise levels. The noise from these tenants is clearly audible outside the building at least 100 yards away. I am suffering from lack of sleep and a great deal of stress because of this behaviour. I have written to the tenants and explained the situation but they merely laugh and say it is not their problem. I have had on 3 occasions had to call out the police due to harassment, stamping of their feet on the floor and once knocking on my door at 1 am and peering through the glass at me. I live alone and whilst not of a nervous disposition am finding this upsetting and almost frightening. I have been in contact countless times with both the landlord and the management agent, neither of whom seem to wish to take any action. They have also been advised on the police call outs and have had copies of some of the noise record logs. I have also contacted the local Environmental Health Department and have had their recording equipment in place (as well as keeping noise records logs for almost the entire 4 months) only to be advised that in their opinion there is no "statutory nuisance" and the problem is caused by poor insulation in the property. I accept this in part for not only is there no insulation the landlord does not even have carpets on his floors but the bare wooden floor boards. However, the noise is excessive by any standards and I know that the people in the house next door have been disturbed by it. There is a lease on the building which is mutually binding on both parties and quite clearly states that there should be some form of insulation on the floors and that there should be no disruption to other occupant(s) - in this case myself - of the building. Additionally, there is a section in the document which states "one household only" and the agent has always placed sharers in the flat as tenants. Also I understand that present tenants have a standard AST which I know contains clauses about disturbance to others, noise and behaviour. Like most people I have to work and through the constant disruption in the my life and lack of sleep find more and more frequently it difficult to function. I feel my only option now is to take action myself but owing to the cost involved would like to know: a. Can I take action against the tenants and/or the landlord (in breach of the lease) and how. b. Is it likely to succeed (I know this may be difficult to answer) c. Is it expensive?