Feedback on this Foundation Assembly
Long-time lurker, recent Prime member, and first time post-er. Zone 5A.
I am in the design phase of a prospective new build looking for feedback starting from below-ground with the foundation.
We are looking to build a single-story home on a slab that minimizes concrete, avoids styrene, and still maintains a continuous insulation layer of R10 under-slab, R20 for the stem wall.
Foamed glass board and aggregate seem like great options, though I do suspect the embodied energy may be considerable, given the kilning required, but we are building a house after all; energy required.
I am attaching a PDF but, here’s the gist of what I am thinking.
– rubble trench with bottom drain (frost depth ~40″)
– high slag/fly-ash concrete footer/stem wall on top of trench
– 6″ foamed glass board between stem and slab
– 6″ foamed glass aggregate under compacted earth slab
– 14″ panelized strawbale walls bear on stem, bridge over board to slab
– geotex under the entire footprint including trench
– poly running between aggregate and slab, wrapping under concrete footer, and back up the outside of the stem wall
Since this is quite literally the foundation of the whole project, I am going to work with an engineer on detailing, but figured I’d look for early feedback here.
Any all thoughts/questions/critiques are greatly appreciated.
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