Foam panels are a core of expanded polystyrene (EPS) between two sheets of composite oriented strandboard (OSB). The panels are stronger than conventional framing and more earthquake-resistant. EPS does not off-gas harmful chemicals nor does it burn or sustain a flame. Because they are pre-cut, waste is reduced and they contain about 75 percent less wood than a framed wall. Structural Insulated Panels (SIP) have higher insulation value, reduce air leakage, and resist moisture and rot. They also act as a sound barrier.