Where to place the vapor barrier in a concrete slab on grade with radiant floor and integral colored concrete?
We are building a 2,200-sq.- ft. single-story concrete slab-on-grade home with hydronic floors throughout and will be integrally coloring the concrete. Stem walls will be poured and then interior slab will be poured. We are installing hydronic PEX directly to the XPS foam, which will be taped, and then placing rebar on chairs above the PEX. The slab will be 5 inches thick with fibermesh such as Stealth 150.
Reading through previous questions and answers and referring to the many articles on where to place the vapor barrier, it appears the expert opinions are to place the vapor barrier, such as Moistop from Fortifiber or Stegowrap, directly under the concrete. However, where should it be placed when the hydronic PEX is being stapled to the foam?
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