Use PreFirred insulation for finishing basements, concrete walls and concrete masonry unit (CMU) walls. It’s a cost-saving solution for interior or exterior applications.

PreFirred interior applicationExamples:

  • Cold, uninsulated concrete walls
  • Concrete masonry unit (CMU) walls
  • Residential basements
  • Commercial/Industrial building CMU above-grade walls


  • Manufactured with expanded polystyrene (EPS)
  • Available in 1½”, 2” or custom thicknesses and 4’x 8’ or 2’x 8’ sheets
  • 1”x 2” solid wood firring strips embedded 16” or 24” on center


  • Interior: Firring strips are used to attach PreFirred to concrete, then used again to attach interior finishes, such as gypsum board or other code-compliant products
  • Exterior: Firring strips are used to attach PreFirred to CMU walls, then used again to attach siding

PreFirred insulation finishing exterior concrete block wallBenefits:

  • No need for framing studs
  • Quickly pays for itself in energy savings
  • 1½” thick sheets provide stable R-6 level of insulation; 2” thick sheets provide R-8
  • Prevents air infiltration
  • Continuous insulation eliminates thermo shorts
  • EPS is resistant to mold
  • EPS is recyclable and environmentally responsible


Read, download or print our PreFirred brochure.

Benchmark Foam, Inc., 401 Pheasant Ridge Drive, Watertown, South Dakota 57201

Phone 605-886-8084   Toll-free 800-658-3444   Fax 605-886-8099

Products Made In The USA!

EPS is a lightweight, versatile, economical, recyclable material that can be tailored to meet changing and complex requirements. Select one of the following topics to learn more: