cellular glass

cellular glass

[′sel·yə·lər ′glas] (materials) Sheets or blocks of thermal insulating material for walls and roofs made from pulverized glass that is heated with a gas-forming chemical at the flow temperature of glass. Also known as cellulated glass; foamed glass.

foam glass, cellular glass, expanded glass

A thermal insulation made by foaming softened glass to produce many sealed bubbles; has a closed-cell structure. Molded into board and blocks, usually with a density of about 9 to 10 lb per cu ft (14.4 to 16 kg per cu m).