Blown cellouse

[JackofAll]

Anyone here who insulated at rafter level with blown cellouse not use a "flying batten"?used to avoid tenting of membrane on outside. Just wondering how important it is to use? Roofer has forgot to include it before slating.

[Omnibuswoman]

We used wood fibre board on the outside of our frame/ roof, with blown cellulose as insulation underneath, then passiv OSB on the inside.