Single Storey Extension/Conservatory

[dave7777]

Hi all I am new here. I wish to extend the back of my semi-detached house my neighbour already has a single storey extension of approx 16' from the house and we have a single skin out house the same length to the lefy of our property with a timber built lean to (which has seen better days) built on the right hand side creating a covered walk way effectivly. Will I need planning permission to fill in the area between the walk way and my neighbours house? An area approx 16' x 14' What I want to do is pull down the lean to and take off the asbestos roof of the outhouse (that currently forms a cloakroon and utility room) build a block cavity wall along side my neighbours wall and put a large patio door across the new outside wall approx 4 metres wide, and put a poly carb type roof on it to keep as much natural light as possible whilst retaining the original outbuilding we have.

Hope that makes sense all comments/suggestions welcome?

thanks

dave