Roof height permitted development

[Cotswoldrunner]

Hi guys looking at an outbuilding 

 

have a question over permitted development. 
 

I am fine on all the criteria but have a question/issue over the roof 
 

I want a flat roof at 3m but the permitted development notes say 

 

it must have a maximum eaves height of 2.5m, a pitched roof no higher than 4m and all other roofs no higher that 3m. 
 

does that mean I can’t have a flat roof higher than the build up of the roof above 2.5m

[Redbeard]

It suggests that you can have a monopitch roof sloping 2.5-3m, but I would suggest a Planning app to get what you really want, if that does not fall under PD. I did that for my shed. Within 1m of the boundary, 3m @: eaves (and ridge height 4m). No problem (except the 8+ week wait for it to be transferred from the 'in' to the 'out' tray!).