Damage caused by another leaseholder
Damage to a leaseholder's property
If a leaseholder damages another leaseholder's property, the affected leaseholder will need to make a buildings insurance claim. An insured peril must have operated and the event must have been sudden and immediate.
Damage to a council tenanted property
If you cause damage to the contents of a tenanted property, the tenant should be able to claim on their own contents insurance policy if they have one.
If the tenant does not have contents insurance there is a possibility that the tenant can claim directly against you as the leaseholder, if the tenant can prove you have been negligent and the issue has been on going for a period of time.