Editing Structural insulated panel (section)

== Materials ==
SIPs are most commonly made of OSB panels sandwiched around a foam core made of expanded polystyrene (EPS), extruded polystyrene (XPS) or rigid polyurethane foam. Other materials can be used in replacement of OSB, such as plywood, pressure-treated plywood for below-grade foundation walls, steel,<ref>[http://greenhome-supply.com/docs/sips/Engineering%20and%20Architectural%20Design%20Guidelines.pdf Engineering and Architectural Design Guidelines.pdf]</ref> aluminum, [[cement board]] such as Hardiebacker, and even exotic materials like stainless steel, fiber-reinforced plastic, and magnesium oxide. Some SIPs use [[Fiber cement siding|fiber-cement]] or plywood sheets for the panels, and agricultural fiber, such as wheat straw, for the core.

The third component in SIPs is the spline or connector piece between SIPs.  Dimensional lumber is commonly used but creates thermal bridging and lowers insulation values.  To maintain higher insulation values through the spline, manufacturers use Insulated Lumber, Composite Splines, Mechanical Locks, Overlapping OSB Panels, or other creative methods.  Depending on the method selected, other advantages such as full nailing surfaces or increased structural strength may become available.