Why is perimeter slab insulation important?

A substantial amount of heat is lost through an uninsulated slab, resulting in cold, uncomfortable floors. Even if the foundation wall is insulated vertically under the slab (Figure 1), significant heat is still lost from the slab edge that is closest to the cold outside air.


Specifically designed to:

  • Provide maximum support
  • Improve strength to siding
  • Eliminate buckling
  • Provide permeability
  • Reduce air Infiltration
  • Increase energy savings
  • Level uneven surfaces


Technical Specifications:

  • Material: Expanded polystyrene (EPS), treated with fire retardant also treated with Borate termite resistance.
  • Density: 1.0 lb./ cu. ft.
  • Flame spread /smoke developed: 0 / 175.
  • Water Absorption: less than 4% by volume.
  • Thermal Expansion: 0.000035 inch /inch/degree F



8 Saratoga Street

Cohoes, New York 12047

800-836-0719 • (518) 237-4100