Use of alternative building methods and materials is on the rise, especially in the residential construction industry. While stick-frame construction is still the norm in much of the U.S., many builders are embracing the use of Structural Insulated Panels, or SIP’s in construction. As concerns over environmental pollution, energy conservation, and affordable utilities attain a critical mass, builders more and more often find themselves working with SIPs.
The typical SIP is a piece of insulating foam core sandwiched between two pieces of OSB, The foam core may be composed of extruded polystyrene or rigid polyurethane insulation, and the boards could use plywood, precast concrete, sheet metal, or magnesium board for the structural facings.
Because SIPS create a continuous thermal barrier, they lack the thermal bridging problem created when using metal or wood studs. The air infiltration and heat resistance problems of fiberglass insulation don’t exist with SIPs. SIP construction tends to be 40% more airtight than stick frame construction, and a 4” SIP outperforms a standard stick-framed, insulated structure with comparative R-value.
SIPs are manufactured in a more eco-friendly way than stick-frame building materials are. The OSB in each SIP is manufactured from younger, faster-growing, under-utilized wood, which conserves trees that would be otherwise be cut down to make dimensional lumber. The foam core in SIP’s is only 2% plastic, much of which is recycled. Because SIPs arrive at the jobsite cut-to-measure and ready to install, there is significantly less waste. Because building with SIPs is easier and faster than with conventional building, the construction time is quicker and the labor costs are lower.
With the increasing interest in environmentally sound home building, it’s a good idea to become familiar with the procedures and techniques of building with SIPs. Whereas you won’t need a worker to cut holes into studs for wiring because the wire chases are pre-cast in the foam, you will need to be extra aware of the plumbing and ventilation fittings. The air-tightness of a SIP structure will keep standing water from roof, window, or pipe leaks locked into the structure, which can cause accelerated rotting and structural collapse.
SIPs are an excellent, eco-friendly alternative to stick-frame construction, but they aren’t perfect. Residential building professionals who are familiar with the specific demands of SIP construction will produce high-quality and eco-friendly results. Which will make them much more marketable than those who aren’t.