SIPs have been our regular exterior wall system since we built our first home in 1995. Structural Insulated Panels are an engineered building system made with two skins of Oriented Strand Board (OSB) separated by a thick Expanded Polystyrene (EPS) core.
Like an “I” beam, you get a very strong wall system without the need for vertical studs running through the exterior walls which are poor insulators and cause heat loss. SIPs are also excellent in that the dew point, where moisture condenses, is inside the living space where circulation systems can safely remove moisture. Other systems that use fiberglass with rigid or spray foam on the outside have dew points inside the wall where moisture can produce mold. SIPs were in development from the mid 1930′s until the 1960′s when they were refined and perfected.
One of the most unique features of Structural Insulated Panels (SIPs) is that there are none of the vertical studs that are found throughout the length of a typical stick built home. Vertical studs are not good insulators… there’s a potential air leak point at each stud and in the fiberglass insulation used. Basically, SIPs make a home function like a thermos, keeping the inside of the home warmer in the winter and cooler in the summer.