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Materials & Specificationsaka: foam board insulationaka: EPSaka: XPSaka: polyiso

Rigid Insulation

In Plain English

Stiff foam boards used for insulation where space is limited or continuous insulation is required.

Definition

Rigid insulation consists of stiff foam boards made from expanded polystyrene (EPS), extruded polystyrene (XPS), or polyisocyanurate (polyiso), used for thermal insulation of walls, roofs, and foundations. R-values range from R-3.8 per inch for EPS to R-7.5 per inch for polyiso. Rigid insulation is used where space is limited and in continuous insulation applications to eliminate thermal bridging.

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