GL-30 is a flame-retardant vapor barrier facing manufactured using a lightweight, white metalized polypropylene film (.00125”), fiberglass reinforcing yarn and natural kraft paper laminated together with a flame-retardant adhesive. 

Johns Manville GL-30 facing is a flame-retardant vapor barrier facing manufactured using a lightweight, white metalized polypropylene film (.00125”), fiberglass reinforcing yarn and natural kraft paper laminated together with a flame-retardant adhesive. GL-30 facing is mold and mildew resistant for added product protection and is typically used as a facing for metal building insulation.