It will depend on what it says in the deeds as to who is responsible for roofing costs for the flats. Sometimes it's the top flat owner, sometimes it's everyone in the block - the deeds really ought to say. In Scotland, roofs will often come under the description of ''common repairs''. In the past, all owners had to agree to work being done before it went ahead. Obviously this caused problems where an owner would refuse. The local council could then demand the work take place, and, if there were still no agreement, the council would have the work carried out and charge the owners on a pro rata basis. As I understand it, new regulations allow a majority vote by owners to be sufficient for work to go ahead. But in any event, if you were liable to a share of costs you should have been consulted beforehand, the work should have gone to tender, and you should have been given an estimate of the cost to you.