Insulation between Rafters

shamsteak

Hi all,

I'm building a new house at the moment and am uncertain of which type of insulation to put between my rafters. I have been looking at the 100 mm Rafterloc stuff, seems quite good but expensive. Somebody has already suggested using frametherm, a type of wool material that will expand slightly to compleatley fill any gaps or joints and it's half the price and the same U value, but it's 140 mm. Does anybody have any experience with either of these or any alternatives?

It might be worth mentioning that i've used Tyvek Supro membrane so am I right in saying i dont need to install roof vents and i only need to leave 25 MM of space between the felt and the insulation?

Any advice at all would be great,

Thanks

Gerry_G

Hi,

Ok Tyvek Supro felt there is no need for vents however if you use RafterLoc you must leave a minimum gap of 50mm or else your roof will release condensation. BUT there is a product called Metac Insulation @20kg density. Put it right up against your felt. Counter batton then slab. U Value achieved at not near the price of rafterloc. Very handy and a goog good job