Back in the fall of 2022 we thought we'd settled on a slab-on-grade foundation. It seemed like the easiest and most inline with MVC principles.
After some more research and back-and-forth with our builder, we've pivoted and decided to go with a crawlspace foundation. There are several reasons:
- Mistakes will be made. It will be a lot easier to fix them with a chase under the MVC than with things cast in concrete. This I am sure of.
- We are getting old. An appeal of the slab-on-grade was the notion of simply using the slab as our floor. But standing on concrete sucks, especially as cartilage has become thinner (or non-existent). A forgiving wood floor on top of a forgiving wooden floor truss — combined with Hush Puppies and Dr. Scholl's inserts — will make everyone happier and healthier.
- We can put some mechanicals down there. We're not sure what, exactly, quite yet. But given the MVC's petite 24x36 figure, even an additional square foot is precious.
Here's the drawing for the crawlspace subslab. Once this is in place, 3" of rigid insulation goes on the interior of the foundation walls, and then a 4" slab is poured on top of the 10mm poly (the yellow part).