Crawl space ON a slab on grade.
Hi Friends.
planning on building a house in northern coastal Maine on existing site of a double wide trailer. Currently, there’s a slab under the trailer. First floor of the house wants to be 4 to 5 feet above grade.
My current thought is to have footings and stem wall to grade. Rigid insulation inside stem walls under edge of slab. Rigid insulation and advantek on top of slab. 2×6 Wall construction on top of stems supporting floor system from there.
given that is the desired height of the main floor, and existing conditions, it seems like this concept would give me some of the best of both worlds in terms of slab on grade and crawlspace. Obviously could also have stem wall poured to 4 foot height, and build floor system on that, but it seems like the 2x construction would be cheaper than the concrete.
I have a little to no information about existing slab, including thickness.
Many thanks for any thoughts
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Replies
nest_builder,
The result sounds good, the process to get there might need some creative solutions. It will be tricky to excavate and form up 4 ft deep stem-walls against the edge of the slab. I would be more inclined to use a FPSF and avoid the digging.
Another question is whether in preserving the existing slab - which once the crawlspace is completed really just takes the place of the optional scratch coat (rat slab) - you aren't limiting the design of the house above?
Yeah, designing the house to save the slab seems to be putting the cart before the horse. A slab that size costs maybe a few thousand dollars.