Hi all
We have recently started going through the process of getting our loft converted, my architect has indicated on the drawings we have to achieve a U value for our pitched roof of .13(Scottish regs). For this he has indicated the following layers.
50mm air gap
125mm kingspan k107
Under rafters 62.5mm insulated plasterboard kingspan k118
I have been advised this is an expensive way to achieve the target u value.
Inwas wondering if anyone out there could advise an alternative way to meet the regs for this.