Warm roof, SIP or PIR between rafters?

[mikert]

Hi Forum,

I've just began blocking my trad build house, and thinking ahead to the roof, floor area ~ 130 M2, L shaped, roof to be @ 33 degrees.

Toying with the idea of using a 200mm SIP roof, but worried about the price. Would there be a massive increase in cost compared to attic trusses with 100mm PIR between and 100mm below rafters?

Thanks in advance,

Mike.

 

[freddiemercurystwin]

The attractive thing about using SIP's be it for the walls or roof is that they're quick. If time is not an issue (ie you are building this yourself) then I would not expect SIP's to provide much if any of an advantage. Its different if you're a developer throwing up 100 houses as quickly as possible.

 

[mikert]

Thanks for reply, no urgency as such, but really hoping to be in by Christmas (Yes - I know, that's what they all say).
I was hoping to save some time, but balancing time saved v extra cost.