Ownership of outbuilding

Hi on our property deeds title register WKY110801 and inspire id 25342747 I believe it shows us to have ownership or a least exclusive use of the outbuilding. However our neighbour title no WYK870209 claims it as theirs but I believe their property ends at the wall behind. I wonder if you have any advice ? 

Hi Emma - your title plan confirms the general boundaries of the title/property and the register your ownership. If you check your register it also refers to the exclusive use of a water closet which is then tinted blue on the title plan
You can also check your neighbour's title plan if you wish to 
WYK110801
Search for land and property information - GOV.UK

Hi Adam I have had a look and their plans do not mention the outbuilding,  either on the house or the land deed.It does mention sharing the other half..I  also found the inspire id no 25342984 which I think shows it in greater detail. Would that be a more accurate way to define it ? 

Hi Emma - if by outbuilding you mean the water closet then that wouldn't be mentioned on the neighbour's title. 
Unsure what you mean by it mentioning sharing the other half 
An inspire ID relates to a specific polygon within our dataset but it's the title plans you should rely upon 

Hi Adam there is a dividing wall halfway up. I have always thought of it as halves but I suppose it technically makes it its own building as it has a separate entrance.My neighbours argument is that her title plan shows a rectangular area , mine is that it is behind the wall of the building.

Emma - it's all about the interpretation of your title plan and the water closet as referenced. For your neighbour it's about what the red outline/general boundaries confirm.
If you are unable to agree then a surveyor (RICS) might be an option provided you both agree to be bound by their reported findings for example

OK thanks for your help.