DIY Doctor UK DIY Forums

Im hoping someone can help. I have a 1907 granite stone house. I have removed all of the old lath and plaster and am looking to insulate everything. For my external walls I was considering framing the walls with 3x2 posts, then insulating with 75mm of kingspan and plaster boarding ontop. I have just been looking at insulated plasterboard and reading about thermal bridging. Would I be better to make my frame of 2x2 posts with 50mm kingspan and 25mm insulated plasterboard ontop?

Any advice is much appreciated.
John

use 2x2 treated timber to frame the walls, insulate with 50mm kingspan , vapour barrier then stapled to the timber, then screw 12.5mm plasterboard

Thank you, should I simply use 12.5 standard plasterboard or go extra and add insulated plasterboard if my insulation is only 50mm? On the assumption that more is always better?