Structural Insulated Panels

A cost-effective, energy-efficient construction system that saves labor, time and cost.

Structural insulated panels are high-quality foam core panels suitable for

many residential and commercial building applications. They are solid, one-piece structural

components that can be used in walls, floors and roofs. Each panel is made of an Expanded Polystyrene (EPS) core bonded between two outher layers of rugged Oriented Strand Board (OSB).

Expanded Polystyrene Foam Core

EPS is an inert, stable cellular plastic with superior insulating qualities. Unlike many other foam products, EPS is "ozone-friendly" - no CFCs or HCFCs are used in the production of panels. Other characteristics of EPS include:

  • Structural Integrity: EPS retains its shape indefinitely. It will not shrink, decompose or disintegrate due to age or weather.
  • Thermal Stability: The insulating value of EPS does not decrease with age.
  • Toxicity: EPS is formaldehyde-free.
  • Low Water Absorption: EPS has a closed cell structure. Its water absorption level is so low that moisture and the elements will not significantly affect its insulation values.

Exterior and Interior Skins

The oriented strand board skins on structural panels are exterior rated Exposure I by the

American Plywood Association (APA).

Energy Efficiency & Comfort

Structural insulated panels decrease cooling and heating costs even more than their high R-rating would seem to indicate, because they form a solid thermal envelope around the structure, uninterrupted by the typical studs, sills or headers. This substantially reduces air infiltration compared with conventional construction techniques. The panels' solid core of insulation also eliminates the convection looping that can occur in the gaps and spaces typical in batt insulation.

Strength & Durability

The strength of structural insulated panels has been proven through rigorous structural testing required by national code authorities, plus their actual performance through more than 40 years of use.

Inspections, Ratings & Reports

Complete copies of all research reports and test results are available on request. All structural insulated panels provided by PanelWrights are in full compliance with applicable building codes and standards.

Insulation Properties

*Calculated R-factors are for the composite panel, and include two sheets of7/16" OSB at .57 each; air films at .68 interior and .17 exterior, and EPS at 3.85 per inch at 75 degrees Fahrenheit and 4.35 at 25 degrees Fahrenheit. For more information on R-values, visit the Oak Ridge National Labs web site at

Nailbase Panels (Retrofit Panels)

Nailbase panels are an easy way to add continuous insulation and air sealing to older homes as part of a comprehensive energy retrofit plan or as an energy conservation measure when replacing siding or roofing. The composite panels consist of rigid insulating foam laminated to a single sheet of oriented strand board (OSB) structural sheathing.

Panels are cut to fit onsite and attached over the existing wall and/or roof sheathing, providing added insulation without disturbing the inside of the home. New cladding is then installed over the retrofit insulated panels. The OSB face serves as the fastening surface for siding or roofing.

Advantages of using Nailbase Panels

  • Various sizes to match design needs
  • Multiple options for substrate and foam
  • Select core type and thickness to match your performance needs
  • Outside installation allows better performance, faster installation, and no disruption of existing wall assemblies, insulation, or mechanicals
  • Detailed to minimize thermal bridges and air infiltration
  • Assembly details that require minimal training