By creating substantial energy savings and reductions in greenhouse gas emissions, the energy invested in the production of structural insulated panels (SIPs) yields an exponential benefit to the environment compared to traditional wood framing, according to a new study published by the EPS Molders Association (EPSMA). The study examines the full environmental impact of building with SIPs, a panelized building system composed of insulating foam sandwiched between two structural facings, such as oriented strand board (OSB). SIP construction offers exceptional thermal performance and low air leakage, saving energy and greenhouse gas emissions over the life of a home or commercial building.
When compared to 2×6 wood-frame construction with fiberglass insulation, SIPs require slightly more energy to produce, but will recoup the difference an average of 9.9 times through reduced heating and cooling loads. The additional greenhouse gas emissions will be recouped over 13 times during a home’s 50-year lifespan. This represents an energy payback period of 5.1 years and a recapture of greenhouse gas emissions in 3.8 years for American homes.
“The architectural and engineering community is looking to life cycle analysis as a measure of sustainability and a determining factor in the specification of green materials,” said Bill Wachtler, Executive Director of the Structural Insulated Panel Association. “With the excellent research conducted by EPSMA and Franklin Associates, the SIP industry can demonstrate conclusively that our products help meet energy and carbon reduction goals.”
In Canada, the results were even more pronounced, returning the energy invested in 2.7 years, and the emissions in 2.7 years as well. The lower relative global warming reduction in Canada is partially a function of the country’s reliance on hydroelectric energy and lower use of coal.
All calculations were based on a representative single-family home built with 6-inch-thick SIPs with expanded polystyrene (EPS) insulation. The wood-frame home used 2×6 framing at 24 inches on center, R-19 fiberglass insulation, vapor barrier and 7/16-inch-thick OSB sheathing. Both homes were finished with wood siding and ½-inch gypsum drywall.
Following a well-established life cycle analysis protocol, engineers at Franklin Associates examined the full energy investment in producing both building systems, from raw material extraction to component production manufacturing and transportation to the jobsite. The energy and emissions calculations included all electricity and natural gas consumption for heating and cooling over a 50-year period.
The study was reviewed and sponsored by EPSMA’s SIPs Work Group, comprised of SIP manufacturers Insulspan, Plymouth Foam, Premier SIPs, and R-Control.
A complete summary of the life cycle benefits of SIPs can be found here.
The Structural Insulated Panel Association (SIPA) is a non-profit association representing manufacturers, suppliers, dealer/distributors, design professionals, and builders committed to providing quality structural insulated panels for all segments of the construction industry. Learn more at www.sips.org.