Insulation
Prior to installing the radiant floor tubing in any application, the area beneath and around the outside edge of the concrete slab must be properly drained, compacted, and insulated. (See Figure 1) If this is not done, the heat that you intend to go into the room will have the option of going into the surrounding soil instead This will cause high energy consumption ($$) and the hydronic space heater size will possibly be too small for the additional heat loss. We recommend a minimum of 1 1/2” or 2” high-density foundation-grade foam board insulation beneath the slab and a minimum of 1” high-density foundation-grade foam board insulation at the edge of the concrete slab. These products are available at your building supply stores.
