simonr

appreciate the cil reminder I am thinking along similar lines but perhaps using pir board between and pavatherm board above rafters to increase Decrement delay...a new concept to me!

I'm new to this forum so apologies in advance for any errors! i'm planning to convert existing barns to our family home and now have planning permission. i'm a structural engineer and have been round block a few times but really don't know enough about latest technology/thinking so will be reading earlier contributions in the weeks to come. Initially i'm trying to understand best way of insulating warm sloping roofs....i'll be stripping pantiles off 75% of structure (retaining ex rafters) whilst retaining a recent reed thatch on remainder. Where stripping pantile roofs i'm thinking insulation over and between rafters (PIR/fibre board combination ?) Where retaining thatch (250mm thick) , i'm hoping i can simply add extra insulation between rafters (75mm deep) perhaps with thin insulated plasterboard as i want to retain exposed purlins/principal rafters i havent read previous threads so apologies if advice repeated elsewhere