Put in planning application for 4m single floor extension with a pitched roof (i.e. a fancy lean-too according to my folks…).

The planning officer has said he’d like a chamfered corner, so looking down on the floorplan it would be something like this (not my plan, just an example that speaks more than I could explain):

Making it a hip roof would be problem as we’d need guttering into our neighbours etc. etc. so is there any way to get a plain pitched roof to handle that?

just an overhang put on at that corner – or go back to planning and ask if they NEED a chamfered corner, not just LIKE one

Is there a neighbours window near that side of the extension. Planning tend to draw a line a 45 degree from the centre of adjoining properties windows as they think neighbours has a right to light plus view from said window.
I have seen this chamfer put into many plans for such reason. With regards the roof you can have a overhang as mentioned above or the corner just gets cut off with out having to put a hip in as that would not follow the plane of the roof.

jimr80 has got it – neighbours window is on that side and the planners think there’ll be an issue with line of sight. We want 4m out so they said we can do 3m on the boundary wall and the full 4m at least 1m in from the boundary.

The planning officer has said he’d like a chamfered corner, so looking down on the floorplan it would be something like this

Is he a SIM card officianado ?

You can have a standard pitch roof over that without any hip or overhang. The roof on plan will be the same as the shape youve shown with the ridge running lengthways in the middle.