layering reflective roof insulation with rock wool stuff

[Helen888]

I just wondered, I've some of that reflective insultation for my loft conversion but want to

layer it with some normal  fibre glass insulation that i might as well

use up. I've been told that the silver stuff needs to go in first

(closest to roof) with fibre glass next before plasterboard - is this

correct?

[legs_akimbo]

Personally I would not use any rockwool type insulation in the roof. Absolutely not for between rafter insulation, as it can get damp if it comes in contact with the underside of the roof or blocks through ventillation. To a lesser extent in an over rafter application, you may be ok if the between rafter insulation is correctly installed and this is merely to beef it up a little.