I’m struggling to use @medeek foundation to model the design I want:
Foundation Cross Section.layout (526.6 KB)
I’m wanting a Frost Protected Shallow Foundation (FPSF).
- Basically a Stem Wall foundation that extends above grade to roughly 30", with continuous insulation including the footing on the exterior.
- INSIDE that will be a slab without footing (piggybacking on the stem wall footing, actually), insulated below with appropriate fill below the insulation.
- Since the crawl space will have both the water supply coming up from a buried (below frost level) lateral - and a holding tank for greywater (once I figure out a way to pump it out!), I plan on conditioning the crawl space to keep it above 40 F.
NOT shown on the picture or layout file is what’s happening above this! But just FYI:
- Sill Plate
- Floor and Rim Joists - 2 x ??? (probably 8 to span 12’ cabin width) - with a SMALL amount of insulation. I don’t mind if the main cabin heat “leaks” into the crawl space, but I still intend to have the crawl space as it’s own “zone” at 40 F!
- 2x4 stick built walls w/ sheathing/insulation on outside to match with insulation on exterior of foundation
My questions are simple:
- How do I model this? I prefer to use @Medeek Foundation, but aren’t wedded to it.
- What do you think of this approach?
I do plan to somehow make this an airtight design (overall), Heated/Cooled via Mini-Split (main area), with Energy Recovery Ventilator (ERV) for the cabin and a couple of through floor vents to keep the air in the crawlspace from going stale! Perhaps the floor vents will be enough to heat the crawl space - at least to the low extent I want it heated!