I am in a unique position to assist, having in fact at one time bought a council house from Falkirk District Council.
Does anyone in your block, or adjacent houses, own their property? - the council had all the gardens surveyed at one time. And they drew up maps showing exactly WHICH part of the garden belonged to WHICH house. Only problem is, they involved the occupants so ( annoyingly) they would say things like "we share that path, it is a common access" or " I own that part as far as the clothes pole" etc etc. Or even worse, "I cut that grass for the old lady upstairs, she doesn't want anything to do with it".
Sometimes the occupants of the adjacent houses weren't even AT HOME when this was done, so they had no input whatsoever.
What it all boils down to is that Falkirk District council will almost certainly have coloured plot plans showing what part of the garden belongs to each house. You might not like what you see though- especially if you want to put up a garage at any time.
Hope this helps. Yahoo answers has its uses after all!!