A thermally insulating bubble pack for use in framed structures, walls, crawl spaces and the like; or wrapping for cold water heaters, pipes and the like wherein the bubbles contain a fire retardant material. The improved bubble pack comprises a first film having a plurality of portions wherein each of the portions defines a cavity; a second film in sealed engagement with the first film to provide a plurality of closed cavities; the improvement comprising wherein the cavities contain a fluid or solid material. The flame retardant-containing bubble pack provides improved fire ratings, flame spread indices and smoke development numbers.