With traditional Oak or Douglas fir frames the frame does all of the structural work and so the infill panels are largely just that, infill. However, this doesn't materially change the way in which they would be built up from our standard suggestions, which you can see below. The main difference is that you need to wrap the structural frame with the VCL membrane so that as this frame shrinks you do not open up huge air gaps. This takes time as there is a lot of cutting and taping of the membrane around the timbers and junctions, etc. and this should be brought round to finish flush with the internal faces of the timber frame.

Once the membrane is installed, the softwood panels and rafters can be installed in the appropriate positions and the membrane lapped on to the inside faces of these panels/rafters. This can then be taped to the air tightness layer on the inside of each section.

In terms of minimum build-ups for the panels in the walls I'd suggest the following:-

• exterior
• external cladding
• 50mm counter-battens
• Ampatex Aero breathable membrane
• 80mm Beltermo Ultra wood fibre sarking board
• 140mm studs @ 600mm ccs, fully filled with SteicoFlex 036 flexible wood fibre insulation
• 11mm OSB3
• Ampatex Sinco vapour control membrane, taped with Ampacoll INT airtightness tape.
• 25mm counter-battens
• 12mm plasterboard
• Interior

This will achieve a U-value of 0.177 W/m2K which would be required by building control.

For the roof I’d suggest the following:-

• exterior
• roof covering
• 25mm battens
• 25mm counter-battens
• 100mm Beltermo Ultra wood fibre sarking board
• 200mm rafters @ 600mm ccs, fully filled with SteicoFlex 036 flexible wood fibre insulation
• Ampatex Sinco vapour control membrane, taped with Ampacoll INT airtightness tape.
• 25mm counter-battens
• 12mm plasterboard
• interior

This will achieve a U-value of 0.134 W/m2K which will just pass through building regs.

Hope that helps.