In for plan check is a site built cold room inside a flower shop. 7x15 size that is steel stud framed with r-19 insulation and showing 5/8ths gyp board on outside wall and 5/8ths green board gyp on interior walls and ceiling. Would this work? All i have ever seen normally for cold room construction is foam panels/EPS and etc. used for the interior insulating materials. Is there anything preventing this to be built this way........I have researched the flame spread charicteristics when foam or EPS systems are used in Chap.26 and do not see anything specific preventing this to be built this way. Perhaps a vapor barrier of some kind should also be required. Just need to know if I am missing something on any code required materials for construction of this cold room for cut flower storage or if the aforementioned green board will suffice? Please also add any other considerations that may be helpful.