Noise
If your neighbour annoys you with intrusive noise, they aren't necessarily breaking the law. Try a friendly approach first - they may be unaware that they are disturbing you. Do this in person, then in writing (keep a copy of the letter/s). If this doesn't work, keep a log of the disturbances, noting the date, time, and duration. If possible, ask other neighbours to write statements confirming your report, then send a copy to the Environmental Health (EH) department of your local authority.
If the EH department decides that your neighbour's behaviour is 'unreasonable' and causing a 'nuisance', they can serve a noise abatement order on them. If your neighbour doesn't comply, they may be fined up to £2,000. EH officers may also confiscate equipment such as music systems. In cases of excessive noise between 11 p.m. and 7 a.m., they can issue a warning and follow it up with an on-the-spot fine of up to £1,000. In a block of flats, your neighbours may also be in breach of the terms of their lease or tenancy agreement. Check what your own lease says.
If the EH department fails to act on your behalf, you can take your report to the local magistrates' court (sheriff court in Scotland) and ask for a 'nuisance order' with similar consequences to those above. Alternatively, you can apply for an injunction in the county court (an interdict in the sheriff court in Scotland) to prevent the noise recurring. In the same court, you can claim compensation for the nuisance you have suffered, though this may be a lengthy process and compensation may be small.
Problems With Dogs
If you are regularly disturbed by a neighbour's barking dog, first have a friendly word with its owners. They may be unaware that the dog barks when it is alone, for instance, and may be prepared to help the dog settle by giving it more exercise or leaving it alone less often and in a larger space. Sometimes a dog is less inclined to bark if a radio is left on at low volume, or if the curtains are closed so that it can't see people passing outside. If the nuisance persists, you can apply to the EH department for a noise abatement order, as above.
If you can prove that a dog is dangerous or out of control, a magistrates' court can order that it be kept muzzled or on a leash, neutered, or destroyed. The owner could also be fined up to £2,000 and prevented from owning a dog for some time to come. Contact the police or the Royal Society for the Prevention of Cruelty to Animals (RSPCA) for advice.
Pests
If your neighbour has an infestation of pests, such as mice or rats, and they find their way into your property, call the EH department and suggest to your neighbour that they do the same. A joint visit from the pest control officer would make sense. If your neighbour refuses, EH officers have the power (after giving 24 hours' notice) to inspect premises for pests that are a health hazard. If they are not admitted, they can apply for a warrant and enter by force. If your neighbour is unable to deal with the infestation because of old age or infirmity, contact the social services.
Trees
Trees can damage foundations - their roots take water from the soil, which may cause subsidence. A tree is the responsibility of its owner, so if you have evidence that your neighbour's tree has been the cause of damage to your property, check whether you can make a claim on your buildings insurance policy and allow the insurer to recover the money from next door. The best policy, though, is prevention- talk to your neighbour about pruning the tree before it gets too big, and come to an agreement on cutting back roots and branches to keep it in shape. If you can't agree, you have a right to cut off roots and branches where they cross your boundary, unless the tree has a preservation order on it or you live in a Conservation Area - check with your local authority first.
If your neighbour neglects to prune trees that overhang your property, despite a written agreement that he or she would do so, you can sue through the county court for the cost of pruning the trees, but in order to claim any more, you would have to prove that damage had been caused.