{"id":"class-b","license":"CC-BY-4.0","data":{"term":"Class B","shortDef":"The middle roof-assembly class under ASTM E108 or UL 790. Oregon R327’s floor is Class B equivalent. Class B is not Class A.","relatedGlossary":["class-a","assembly","covering"],"relatedCategories":["roofing"],"relatedStandards":["astm-e108-ul-790"],"relatedGuides":["r327-vs-cwuic","class-a-covering-not-a-bag"],"author":"grayson-graham","reviewStatus":"draft","lastVerified":"2026-08-23T00:00:00.000Z"}}