Structural Insulated Panels, or "SIPS"

Structural Insulated Panels (SIPS) are an advanced method of constructing walls, roofs, and floors. SIPS consist of rigid insulation (usually expanded polystyrene) sandwiched between two sheets of OSB or plywood. Little or no structural framing penetrates the insulation layer. Panels are manufactured in sizes up to 8ft. by 24 ft.

In the field, the SIPS panels are joined in one of two ways and the choice affects thermal performance. The first way is to use wood spacers at the joints. These spacers allow thermal bridging but they are spaced no closer than about 48 in. The second way of joining SIPS panes is to use an OSB spline. With this technique, the insulation is notched or routed just in back of the OSB panels on each side. An OSB strip is then inserted into the pocket on each side of the panel and the assembly is fastened together with wood screws.

SIPS offers the best R-Value (thermal resistance rate) are available in five (5) thicknesses. Each thickness has a different efficiency rate. The following R-Values were calculated at 40 degrees.

R-VALUES ON SIPS

4” INCHES=R16

6” INCHES=R24

8” INCHES=R31

10” INCHES=R39