Cavity walls= 50mm foil backed kingspan
Hillside walls= 100mm internal kingspan
When I say 50mm insulation, these walls all have 50mm in the cavity and another 50mm internally.
In terms of attic I havent quite got there yet to determine whats going in, but we have taken the roof off and a new one is going on so we can do what we want here.
Windows are South-West facing (will get a lot of wind) and double glazed aluminium.
In terms of the MVHR, obviously its easier to fit this prior to testing the house for air tightness, is there a way to determine before hand if we will achieve the values you state please?