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The Ultimate Dual Purpose Construction Grade Foam

Our proprietary process and continual improvements to our ICF system led to our development of FlexxBoard25 – a rigid foam insulation board that provides improved performance over XPS (Extruded Polystyrene) boards – at a lower cost.  Even better, when used under concrete, FlexxBoard25 bonds to concrete forming a superior thermal barrier, helping to prevent shifting, heaving and cracking.

FlexxBoard25 is the perfect foam insulation board to use above or below ground:

  • Under-Slab Thermal Barrier – When used as a thermal barrier before pouring concrete, FlexxBoard25 bonds to concrete – reducing heat loss and helping to prevent possible frost heaving.  It helps extend the life of concrete driveways, sidewalks, patios, basements, shop and garage slabs, and basements.
  • In-floor Heating – FlexxBoard25 can be used as a thermal barrier beneath concrete slabs when installing radiant floor heating systems – preventing heat loss to the ground while promoting even heating.
  • Perimeter Insulation – When used around the perimeter of a poured concrete or block wall foundation, FlexxBoard25 prevents heat loss.  In shallow foundation designs, using FlexxBoard25 around the perimeter of a poured concrete slab will help prevent frost penetration and frost heaves.
  • Custom Fill Applications – FlexxBoard25 is simple to use in structural fill applications – custom shapes can be fabricated by LiteForm or be delivered in blocks and fabricated on site.
  • Roof Applications – FlexxBoard25 is an exceptional insulator and fill material for all roofing applications.

FlexxBoard25 offers many advantages at a lower cost than the competition:

  • Energy efficiency
  • Helps eliminate frost heaving and concrete cracking
  • Increases the structural integrity of concrete in both interior and exterior applications
  • Bonds to concrete and will not separate like other foam products
  • Moisture, mold and mildew resistant
  • Will not rot, deteriorate or degrade over time, sustaining its R-Value
  • Environmentally conscious formula uses a smaller portion of petroleum to make compared to other foam products
  • Made of non-toxic materials that do not off-gas like other foam products
  • Superior dimensional stability assures structure remains tight and energy efficient over life of building
  • Acts as sound deadening, quiet barrier

FlexxBoard25 can be found at most building supply centers.

Frost Protection that Bonds to Concrete!

FlexxBoard25 bonds itself to concrete resulting in a stronger more durable insulation. The foam will not rot or deteriorate when exposed to natural elements.

Competing colored foam boards (extruded Polystyrene) are known to separate from concrete because of its smooth finish. This will ultimately diminish r-value and result in the need to replace the concrete in the future.

FlexxBoard25 Literature

Flexxboard 25


Description and specifications for FlexxBoard25 Insulating Foam Board

Product FlexxBoard25
Overall Dimension 48″ x 96″
Density Classification 2.0 pcf
Staple Pull out Strength

29 lbs.

Thermal Resistance (R-Value) @ 75º 2 inch = R-9
Strength Properties, minimum
Compressive Strength
Dimensional Stability
Oxygen Index
Thermal Conductivity K Factor @ 75º F
psi – 32.8

Moisture Resistance, Maximum
WVT (water vapor transmission
Absorption (vol.)

perm./in. – 2.65
% – 2.4