The Wildlife and Countryside Act 1981 provides protection for all species of bat found in the United Kingdom. It is illegal to kill, or even disturb, bats in their roosts.
If bats are present, and there is a possibility of them being disturbed, you should consult
Bat Helpline Tel: 0845 1300 228
Natural England Tel: 0114 241 8920,
Scottish Natural Heritage Tel: 0131 447 4784 or
Countryside Council for Wales Tel: 08451 306229.
They will arrange for a person to visit the site and advise on the best course of action.
Bats may only be handled by those licensed to do so. 
Pest Information from the British Pest Control Association.