Sub Basement Crawl Space
In the planning stage for steep slope home in North Carolina. After the topo survey results came in today, it is obvious we will need a crawl space under the lower level(will have main floor, lower level, then crawl space below due to steepness of lot). The foundation will step down on the sides. The way the builder describes it, they generally leave dirt floors, then encapsulate and condition this space and spray foam the walls. Seems to me I would rather treat this crawl like a mini-basement. It might require another footing across the space with a stem wall, but then I could pour slabs as the foundation steps down, and could add foam board/vapor barrier beneath them like a proper slab. Then I could insulate the walls with foam board just as I would any conditioned basement space. At the downslope side, this “crawl” could be 8 or 10 feet tall. Am I missing something here? It seems like a large area beneath my house to leave with a dirt heat sink.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part