Hi I am a retired auto engineer with loads of motorcycle, cycle and other projects as well as a caravan that need sorting and storage space.
I am surrounding and ol 18 x8'6" garage with another higher wall to provide more storage space and adding a 3m carport to the side for the caravan.
The problem I have is achieving 2.5m eaves to the neighbour sides with a 3m flat top roof without needing planning permission .
I think I can do it with a Mansard roof but having trouble finding confirmation and structural plans.