2 lb density EPS is an economical insulation for radiant floors. The 2 lb density EPS has an R-Value of 4.35 per inch, so a 2.3” thick panel provides an R-Value of 10. The EPS is typically less expensive than extruded polystyrene and has the same compression strength. In this photo, the contractor in Palmyra, NY, used 175 sheets of EPS to insulate this 5,600 sf building. The PEX tubing is wired to the woven wire, which sits on a poly vapor barrier covering the insulation. Universal Foam Products ships EPS from over 60 locations in the United States.