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How would you insulate between old and new slab?
Live in NY, I have a early 1900's carriage barn with about 4-6 inches of concrete with rebar, no vapor barrier (not sure when the floor was poured) No Cracks.
I took off the old barn doors and put on patio doors, raising them up 4 inches, (max I could get for headroom)
I'm going to install radiant and pour new concrete with color as a finished floor, just wondering what some opinions are here.
Insul tarp vs. plastic and foam vs other options for 4 inches of pour room.