The skins act like the flanges and the rigid core similar to the web. In short, the three components work together, rather than against one another. This composite assembly yields stiffness, strength and predictable responses. Not only do test results show panels are stronger, but real life natural disasters have proven it time and time again. Fire requires three components, fuel, ignition and oxygen.
SIPs have no 'air' within their solid cores of insulation.
Sips have passed every standard fire test that is required of wood based or type V construction. A key element of fire safety is protection of the SIPs and any other underlying structure with thermal barriers like gypsum wallboard. All of the advanced technology building systems require some sort of mechanical ventilation. These systems bring fresh air into the home or building and exhaust the moisture laden or stale air to the outside. Often they can be combined with filter systems or other fresh air devices.