In any case, the true meat of the issue would be that the noncombustible materal shall be of APPROVED content, which implies it must be acceptable on the BO. Open up to interpretation; “to facilitate the motion of liquids”, the commentary invitations this as to avoid the accumulation of liquids; https://garageceilingstoragelift86420.wikissl.com/1437423/5_simple_techniques_for_motorized_garage_storage_lift