Permitted planning??

[James Webste]

Hi, New here and couldnt find any info in regards to what Im after, and the local planning cant answer either, so hoping someone here can help!
I am looking to build a 2 storey extension at the rear of our property. Looking at permitted planning the eaves must be less than 3m if within 2m of the boundary. No where seems to state if I can have 3m within the boundary, then at the other end of the extension (8m from boundary) whether they can then be higher?
Also, if i was to go single storey until outside the 2m boundary, then built a 2nd storey, could those eaves be over 3m?? I have (I think!) attached a picture to try and explain what I mean by scenario 2. Any advice would be appreciated. I have looked high and low, and tried to contact various people with no clear answers! Thanks in advance. JW

 

[Nakajo]

A planning application would be required for a two-storey extension

 

[tony1851]

A planning application would be required for a two-storey extension

If it's on the back, not necessarily.

@op; just seen your pic; that would need planning permission because it falls foul of A.1 (g) ie part of the extension is within 2m of a side boundary and the eaves are higher than 3m - this applies even if the part with eaves higher than 3m is more than 2m from the boundary.