The additions to my parent's place is all post and beam and SIPs. They've been holding up well for over a decade. I don't know the R values, but the roof panels are 8" thick, wall panels are 6" thick, and floor panels (where they used them) are 4" thick. My folks turned a ~2200 Sq Ft '50s cinder block house into a ~8000 Sq Ft house by building above and to 3 sides of the existing house. All of the additions are SIPs and pine beams.
My folks bought 20 acres of 30 year old pine and partnered with a small, local, wood mill to fall the trees mill the beams and some of the finish lumber. Dad used a place in northeast AR to laser all the 1/4" steel brackets for putting the giant erector set together. Most of the work was done by dad, family, and me, dad hired plumbers, electricians, stone layers, etc. but the structure was all us and a few hired laborers.
Most of it was handled with farm equipment we already had, dad's got a Swinger front end loader, but he did lease a giant New Holand telehandler for about a month, and the tall stuff required a crane.
SIPs went together simple enough, the foam is the same thickness as standard lumber, i.e. 4" foam is the same thickness as a 2x4 is wide. Dad had some electric "branding irons" similar to electric charcoal starters, one for each thickness of panel he was using. The branding irons had guards on them that could be set at various depths, so you set the depth, then "cut" the foam from the edge forming a groove that allows you to fit lumber in. Sandwiching lumber back to back allowed you to fit panels edge to edge, kind of like giant tongue and groove panels. There were a lot of really long screws used too.
The roof SIPs panels were felted with tar paper, and corrugated steel roofing was attached directly to them.
That's most of what I remember, if you have any more specific questions, I can try to answer, or at least ask dad. I know I have some finished pictures, but I might have some during construction pictures too, if you're interested I can see what I can dig up.
