Planning permission or not?

I've recently bought a house and I'd like to move the patio doors. They're currently on the side of the house and I'd like to put them on the back wall and block in the old door. I will of course consult an architect to check if I need a supporting beam above the new doors, but I just wondered if I would also need planning permission to do this. Any ideas?

The new door would look over the garden, not over anyone's property if that makes a difference.