STYROFOAM™ Brand Square Edge Insulation (U.S. Only)

A Type IV extruded polystyrene foam insulation with squares edges on all sides.

Used In

  • Commercial and residential applications
  • Commercial foundations and building floor slabs
  • Residential attics, foundations/slabs and crawl spaces
  • Against commercial interior walls and exterior foundation walls in above- and below-grade applications
  • Under the slab or over the deck or subfloor
  • Suitable for use in pervious, semi-pervious and practically impervious soils

Product Advantages

  • Contains an average of 20% pre-consumer recycled content certified by UL Environment Inc.
  • Square edges help ensure energy efficiency and minimize on-site cutting and waste
  • Superior water resistance
  • Long-term thermal performance
  • Minimum compressive strength of 25 psi
  • Helps protect foundation damp-proofing and waterproofing, especially during backfilling
  • Provides a secondary barrier against groundwater leakage
  • Freeze-thaw cycling of the foundation wall is minimized, reducing the potential for cracking
  • Helps reduce the potential for condensation

Typical Physical Properties

These properties are typical but do not constitute specifications.

STYROFOAM™ Square Edge

Nominal Board Thickness(1), in R-Value(2) Board Size, ft Edge Treatment Min Compressive Strength(3), psi
.75 3.8 2 x 8 / 4 x 8 Square Edge 25
1.0 5.0 2 x 8 / 4 x 8 Square Edge 25
1.5 7.5 2 x 8 / 4 x 8 Square Edge 25
2.0 10.0 2 x 8 / 4 x 8 Square Edge 25
2.5 12.5 2 x 8 / 4 x 8 Square Edge 25
3.0 15 2 x 8 / 4 x 8 Square Edge 25

(1) Not all product sizes are available in all regions.

(2) R means resistance to heat flow. The higher the R-value, the greater the insulating power. R-values are expressed in ft2• h•°F/Btu. R-value determined by ASTM C518.

(3) Vertical compressive strength is measured at 10% deformation (5% for STYROFOAM™ Brand PLAZAMATE™ Insulation and for STYROFOAM™ Brand HIGHLOAD 40, 60 and 100 Insulation products) or at yield, whichever occurs first. Since STYROFOAM™ Brand Extruded Polystyrene and Dow polyisocyanurate insulation products are visco-elastic materials, adequate design safety factors should be used to prevent long-term creep. Adequate design safety factors are needed. For more information visit our Answer Center.

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