I recently met with my good friend Bill Matiko to discuss his recent home project. Bill is building a beautiful home on a small acreage just outside of Saskatoon. Although he never planned for his home to be a Net Zero Energy home, Bill carefully designed his home to be energy efficient.

A Structural Insulated Panel (SIP) is a panel composed of expanded polystyrene insulation (EPS) board laminated between two sheets of oriented strand board (OSB).

I was researching the use of SIPs as a construction strategy for super insulated homes (R50~60 walls, R90~100 ceilings). Bill had used SIPs in his home and I wanted his opinion.

Bill reported that the SIPs were a charm to install. He took a one day class on how to install them and he and one other guy were able to set up all of his walls in less than three days. He felt that the materials were superior in quality and that they were very well engineered for easy installation. No vapor barrier is required and the walls were designed for easy installation of electrical systems.

SIPs provide a higher insulation value than regular wall construction. The specifications of one leading manufacturer indicate that a 6.5 inch SIP has an R value of 24. This is about a 25% increase in thermal resistance over a typical 2×6 wall construction that would have an R value of about 19.

SIPs are more expensive than standard wall construction.

The maximum R value I have seen available is a 12.5 inch thick SIP that would have a thermal resistance of R46. Some manufacturers indicate that they can build any dimension but the cost of special orders may be prohibitive.

SIPs are a good option when designing your Net Zero home. Pay close attention to the costs and be sure to compare apples to apples.