as for cold climate rammed earth houses are pretty much the same and they work in cold areas or you could do an earthship design.
as for above ground structural …use shipping containers…. then 4 inches of 3/4 minus gravel then 7 inches of spray foam. You can get a container for 2500 and to do rest is fast if you know what to do with plasma cutter and welder. and you get a r 60 house at 320sf per container.
you use the sheets you cut of inside areas to plate the outside walls you get a 12 inch all sandwich 1/8 steel 4 inches of gravel 1/8 steel 7 inches spray foam then your finish.
A slightly different version quarried basalt 12-8 inches thick then 7 inches spray foam then 1/8 steel 6 inches of gravel then 1/8 steel painted i use the steel a a thermo conductor to help heat the house. but the stone work is pricey but you have your own castle ha ha.