I was going to use SIPS, but the company messed me about, so I'm going to build it the American way.
I am discovering, however, that the Americans don't agree on how it should be done! Traditionally it has been 2x4s on 16" centers; sorry, I mean 4x2s on 16" centres. But sometime in the latter part fo the 20th Century the US government actually did some research and came up with Advanced Framing (AF). 2x6s instead of 2x4s, and on 24" centres. So it's about the same amount of timber (50% wider but 50% further apart) but all the trusses sit directly on the studs so there is no need for a double top plate. Also you can get 50% more insulation in the walls.
The proponents say that AF is a no brainer, detractors take the "it ain't broke so why fix it?" stand. I'm inclined to go the AF route, not least because it involves fewer pieces to manhandle, even if they are bigger and heavier.
This is a workshop rather than a dwelling, I want it cosy to work in but not boiling. So I think I'm going to have 100mm insulation in the walls. That will leave me an air gap and I can have recessed electric sockets without having to cut away the insulation. If I need to install another socket somewhere, I can cut a hole and get my hand in to fish the cable out, too.
I know it is heat insulation rather than sound insulation, but it is bound to help and it's not as if it is built on a party wall with the neighbours living room. It could hardly be further away from the houses.
While the slab cures I have to draw up some construction drawings so I can get a cutting list. So far I have only a concept drawing. Anyone here an expert on roof trusses? I could do with some input.
My body is starting to complain again. I've hurt my wrists when I fell, as well as scabbing my knee