The concept of a structural insulated panel began in 1935 at the Forest Products Laboratory (FPL) in Madison, Wisconsin. FPL engineers speculated that plywood and hardboard sheathing could take a portion of the structural load in wall applications. Their prototype structural insulated panels (SIPs) were constructed using framing members within th...e panel combined with structural sheathing and insulation.
The panels were used to construct test homes that were continually monitored for over thirty years, then disassembled and reexamined. During this time, FPL engineers continued to experiment with new designs and materials.
Famed architect Frank Lloyd Wright used structural insulated panels in some of his affordable Usonian houses built throughout the 1930’s and 1940’s. SIPs took a major leap in technology when one of Wright’s students, Alden B. Dow, son of the founder of Dow Chemical Company, created the first foam core SIP in 1952.
By the 1960’s rigid foam insulating products became readily available resulting in the production of structural insulated panels as we know them today. The Structural Insulated Panel Association was founded in 1990 to provide support and visibility for those manufacturing and building with this emerging building technology.
In the 1990’s SIPs saw the development of advanced computer aided manufacturing (CAM) technology. Using these systems, computerized architectural drawings (CAD drawings) can be converted to the necessary code to allow automated cutting machines to fabricate SIPs to the specific design of a building. CAD to CAM technology has streamlined the SIP manufacturing process, bringing further labor savings to builders.
Today SIPs offer a high tech solution for residential and low rise nonresidential buildings. Advances in computer aided design and manufacturing allow SIPs to be produced with amazing accuracy to deliver flat, straight, and true walls. SIPs are now made with a variety of structural skin materials, including oriented strand board (OSB), treated plywood, fiber-cement board, and metal. SIPs are available in thickness from 4-inch and 6-inch walls, and thicker roof panels up to 14-inches, depending on climate conditions. Many manufacturers also offer curved SIPs for curved roof applications. The design capabilities, exceptional strength and energy saving insulation make SIPs a twenty-first century building material for high performance buildings.