roof vents

[NATHAN01]

iv recently reroofed a lean too roof with 3/4 ply and had a company felt it for me my question is

i am starting to put up the ceiling inside now and was wondering do i need to put some kind of roof vent in i am using 4" kingspan in between in ceiling joist and there will be a gap from the top of the kingspan to the roof of about 3" does it need to breath or will it be ok

 

[noseall]

Had you asked this question before ply and felting the roof, you could have fitted a less expensive 'warm deck' roof.

Now in order to avoid retro-venting, you should fill the entire void with kingspan.

Incidentally, kingspan supply a ply bonded insulation board specifically for warm deck roofs.

 

[NATHAN01]

yr it was me before but did nt sak the same question i spoke to a experienced builder today and he said i dont need to put vents in if i use 4" insulation and use foiled back plaster board it ll be fine he has more than 30 yrs of building behind so would any one agree with that advice