Thank you - I'm very sorry for the delay in replying to you. I had to take a phone call which took some time. I am grateful for the above information. Based on what you say the wall would belong to your parents property as they paid for it but it may be difficult to evidence this at this point.
The problem however arises from the length of time the neighbours have had the roof secured to the roof. Because they have installed the roof more than twenty years ago they will no be able to claim a right of support by long use under the Prescription Act unless you can show that they attached it to the wall by agreement with your parents. If they did so with your parents express permission, then this permission operates as something called a licence and prevents a right being acquired under the Prescription Act because a licence can be withdrawn at any time. It would be for you to prove the existenec of such an agreement though if denied by the neighbours - a written agreement is best but other evidence such as independent witness evidence can be relied on instead. I appreciate this could be difficult after so long.
If the neighbours claim they have a right to maintain the roof as a result of more than 20 years use, and can prove it has been there for 20 years or more then you would need their permission to remove the wall or at least the section of wall on which the roof rests. If you dispute that it has been there for 20 years, it is for them to prove that it has been in order to claim such a right.
The starting point is likely to be for you to speak to the neighbours and advise that you will be removing the wall and ask that they make alternative arrangements for the support of their roof. They may be unaware of their potential above rights or you may be able to come to some arrangement. If they refuse you can consider advising them they have no right to use the wall as support and hope that they accept this. If they are aware of the above 20 year rule you can put them to strict proof that they have had the roof there for 20 years or more and in addition if you can find evidence of permission by your parents, you can use this to block any claimed right.
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