I am going to build an energy efficient home and would like to use a monolithic slab. I have no experience with these, but here is my situation:
we are going to build at 8200 feet in the Sangre de Cristo mountains of Colorado. The site is basically rock ranging from pea gravel size to 10a stone, with some larger ones. The dirt is so compacted and dry that in a thirty minute digging session with a post hole digger, good sharp spade, and my steel pry bar I barely managed to go 14" deep. There is virtually no moisture in the soil.
In looking at the depiction of a frost protected slab, I am considering a five bag mix with fibre reinforcement, with three rebar lines around the perimeter. The slab would be 4", with an 18" by 8" "footing" around the perimeter. There would be a layer of polystyrene tongue and groove 2" thick for insulation under the slab, and one inch under the "footer" and outside edge of the cement.
This would be our experimenta project as our garage and studio. The building would be 26x28 with R40 walls, R60 ceiling. We would use engineered 8-12 pitch trusses, with heavy asphalt shingles ( withstand 110 mph winds),
Can anyone out there tell me whether or not this is a good plan? I would really appreciate some help on this one.