Expanded Polystyrene Foam Board Insulation Fire Resistant

1 in x 4 ft x 8 ft.

Expanded polystyrene foam board insulation fire resistant.

This foam board insulation is the rigid pink or blue panels that can be found at home centers in many different thicknesses. Like practically all organic building materials polystyrene foam is combustible. Like all organic building materials polystyrene foam is combustible and does react to fire resulting in the decomposition of styrene and the release of carbon monoxide smoke and water. It is denser than eps and provides more r value with a rating of 5 per inch of thickness.

Since most fire codes call for a minimum of half hour fire rating over foam insulations paneling would probably not provide a sufficient fire barrier over the foam insulating board. Astm c578 standard specification for rigid cellular polystyrene thermal insulation addresses the physical properties and performance characteristics of eps foam as it relates to thermal insulation in construction applications. Exposed foam board insulation fire hazards. However the burning behaviour of eps depends largely on end use conditions and whether the eps material is with or without a fire retardant additive.

This q a article discusses the requirement for a fire resistant covering for foam and foam board board building insulation. However in practice its burning behavior depends on the conditions under which it is used as well as the inherent properties of the material.