Our Laminated Panels have earned the Energy Star rating.

Energy Efficient Homes Have Higher Market Value

A new study funded by EPA concludes that energy efficiency substantially increases the market value of homes.

This peer-reviewed study, “Evidence of Rational Market Values for Homes Energy Efficiency,” conducted for EPA by Rick Nevin and Gregory Watson of ICF, Incorporated, was published in the October 1998 issue of The Appraisal Journal. The study showed that:

• Energy-efficient homes have a higher market or resale value regardless of how long you own your home.
• Home value increases $20 for every $1 reduction in average annual utility bill.
• A typical ENERGY STAR HOME reduces utility bills by $35 per month or $420 a year, and, on average, these annual savings will add $8,400 to the market value of the home.

According to the Structural Insulated Panel Association (SIPA):

The foam plastic core of a SIP provides its insulating properties. Depending on the type of foam used (eg., EPS, XPS, polyurethane or isocyanurate), R-values are in the range of approximately 4 to 7 per 1 inch of foam thickness. This results in superior energy performance characteristics in walls and roofs. For example, a 4 inch thick SIP wall is often used as a substitute for a 2-by-4 stud wall, also 4 inches thick overall. Both have 3 inches of insulation. The SIP wall has insulation R-values of 14 to 25, where as the stud wall with fiberglass or mineral wool only has R-values of 11 to 15.

The overall R-value of the stud wall must then be down-graded to take into account the part of its area taken up by framing, where there is no insulation. This is significant – up to 25 percent. The core of a SIP, which usually has no stiffness between spline, is filled entirely with rigid foam. Moreover, when SIP structures are compared to stick-built structures there are fewer gaps, less settling or compression, less moisture absorption or dust saturation, and fewer cavities that permit convection or air circulation. All these characteristics would reduce insulation performance.

The results are evident in both quantified and empirical data. The overall R-value of a conventional wall with 2-by-4 studs and 3 inches of R-13 fiberglass, as indicated in the Thermal Envelope Compliance Guide to the Model Energy Code, is R-13.1. For example, an equivalent SIP wall with 3 inches of extruded polystyrene foam (R-value = 17.5) is R-20.

But these quantified figures do not tell the entire story. In the real world SIPs appear to outperform the conduction resistance of conventional walls even if they are assumed to be the same in R-values. This may be due to the differences between foams and fibers in the degradation items that are no included in R-value calculations, like gaps, moisture, dust, settling and others.

This was clearly illustrated in a recent field test conducted by the Florida Solar Energy Center (FSEC) under sponsorship of the US Department of Energy. Two identical houses were built side by side in Louisville, Ky. They were built simultaneously by the same builder. One had conventional framing, the other was built with SIPs. However, wall and roof thickness were adjusted so that both had the same calculated R-values. Both houses were monitored for heat loss performance, and the SIP house dramatically outperformed the frame house. More importantly, efforts to forecast seasonal heating energy savings showed a 14 to 20 percent savings for the SIP house in Kentucky’s climate. In the published report, the researchers stated that “…there seem to be other factors, which remain unaccounted for, which cause the panel house to use less heat energy.” Homeowners throughout the US are experiencing benefits through lower heating costs, draft-free houses and greater comfort.

Numerous SIPA members, for example, have cited testimonials from owners of SIP homes whose fuel bills have consistently been 40-60 percent below those conventional construction homeowners.