flat roof confusion

[donnyt]

hello all

I have just finished the block work on my 2 storey extension and am intending to put a flat roof on it.

When doing a warm flat roof does this have to have an upstand ? or can the insulation finish flush at the exterior block work, wasn't sure if you have to have an upstand to prevent cold air bridging ?

Thanks

 

[freddiemercurystwin]

http://www.planningportal.gov.uk/uploads/br/masonry_cavity_wall_insulation_illustrations.pdf page 22

 

[donnyt]

lovely .... thanks