Historical: XPS Insulation (extruded polystyrene) - 2015
This information reflects our best understanding of product composition in 2015.
ASTM C578 defines extruded polystyrene (XPS) thermal insulation as a, "cellular plastic product manufactured in a one stage process by extrusion and expansion of the base polymer in the presence of blowing agent(s) resulting in a product which is...
More about Historical: XPS Insulation (extruded polystyrene) - 2015
ASTM C578 defines extruded polystyrene (XPS) thermal insulation as a, "cellular plastic product manufactured in a one stage process by extrusion and expansion of the base polymer in the presence of blowing agent(s) resulting in a product which is rigid with closed cellular structure." XPS foams fall into ASTM C578 Types IV, V, VI, VII, X, XII, and XIII. Rigid XPS foam boards contain flame retardants in quantities sufficient to meet standards outlined in the ASTM standard. This CP describes unfaced, rigid XPS foam insulation boards suitable for a range of insulating applications with a minimum compression strength of 40 psi.
A more up to date CP is available here: https://pharos.habitablefuture.org/common-products/2078867.