I have now studied the Deed.
I note (first page of the Deed) that the right of way grants the owner of the Coach House a right of way on foot with or without animals for the purpose of gaining access to the garden. It then further states that this right of way is for "all purposes connected with the use occupation and enjoyment of the property as a private dwellinghouse". As the grant of the right of way is "FOR ALL PURPOSES CONNECTED WITH THE USE OF THE PROPERTY" then I'm afraid to say that just because an extension has been built on what used to be part of the garden does not prevent the neighbour from continuing with their use of the right of way. I agree that the wording stipulates "for the purpose of gaining access to the garden" but this wording was to show the physical dimensions of where the right of way was running, as opposed to the PURPOSE for which the right of way was granted. Any right of way attaches to a Property, and the further wording stating that this Right is for "all purposes connected with the use of the property" does mean that the neighbour's right of way can be used for any purpose, provided it is to gain access to and from the Coach House.
As regards ***** ***** of way not having been used in recent times, I am afraid that the non use of a right of way is no legal basis to say that the right of way has been "surrendered".From a legal point of view, it is almost impossible to prove that someone has given up their right to use a right of way, unless that person has done some physical act to prevent the right of way being used and even then, the Courts have decided that the right of way could be "resurrected" if that party then removes the physical barrier preventing them from using the right of way. There has also been a Court case which decided that despite a right of way not being exercised for over 100 years, did not mean that the right of way had been surrendered.
Therefore, I am sorry to say that your neighbour does continue to have a right to use the right of way, and the fact that he will be using it to gain entrance to an extension, as opposed to the garden, does not make any difference, as they are still using it for the purpose of gaining access to the property and hence it is for the "use of their property".
I am sorry this s not the answer you were looking for.
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