Styrofoam

Styrofoam is a trademarked brand of closed-cell extruded polystyrene foam (XPS), commonly called


Styrofoam is a trademarked brand of closed-cell extruded polystyrene foam (XPS), commonly called "Blue Board" manufactured as foam continuous building insulation board used in walls, roofs, and foundations as thermal insulation and water barrier. This material is light blue in color and is owned and manufactured by The Dow Chemical Company.
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