whose fence is it

[G Appleyard]

If I put trellis onto my side of a neighbours fence (which has been built on my property) I am within my rights to keep it there or do I have to remove it?

[moonacre]

If it is your neighbours fence then I don't believe you have a right to fix anything to it unless your neighbour has given you that right. However, I'm a bit confused about the "built on my property" part. Your neighbour can not errect a fence on your property without your permission. If you have given permission then be very careful as this may give your neighbour the right to claim the property fenced off as his/her own. At the very least it would give you big problems when you come to sell your house.