New radiant slab in old home — how to save ceiling height?
Problem: We can’t use 3” foam over the footings, if we want to have the same ceiling height as before. The old slab was 4” thick and rested directly on footings. So 4” of depth is all there is, to divide between the new slab and the foam that will go under the slab (and over the footing) — if we want to keep the head room we had before. The concrete contractor is uncomfortable to pour a slab less than 3” thick anywhere. This leaves only 1” for foam over the footings.
Any thoughts? Is there some technique we can use to get the slab 2” thin in those areas? Or are we doomed to lose ceiling height by raising the slab?
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