Hi all, building a new house in Florida and I’m driving myself crazy with the stem wall to slab connection. ICF construction, ICF stem wall because it’s easier for me to do myself, and sandy soils. I’m raising the slab up about 3′ just to be safe from flooding or else I would just do a simple slab on grade which is what I am familiar with from past builds.
I’ve attached a PDF of different options for an ICF stem wall to slab connection or non connection. I see pros and cons to each, but wanted to get some expert advice.
Floating slab – I worry about the interior bearing walls settling at a different rate in the house, but thinking of this for garage floor which is at a lower elevation. It would seem there shouldn’t be much capacity to settle though with 32″ of backfill if it is well compacted. With that pressure all being driven down, I got thinking of the possibility of the footers trying to move laterally, so I thought of the next idea (I’m guessing continuous steel around the corners prevents this, but like I said, I’ve been thinking too much).
Doweled slab – I like the idea of tying the slab into the wall with steel to prevent any movement of the stem wall laterally, but I worry about creating pressure points and cracking concrete in the wall or slab.
Full pour over or 2-3″ notch – The notch method is how it is typically done around here when I see block stem walls built (4″ notch) and is the way I am leaning, possibly with a rebar or wire mesh grid.
As always, thanks for the advice.
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