Abstract: A structural weathertight enclosure for conveying systems and the like includes an outer shell having a pair of spaced apart, opposite sidewalls formed of one or more sheet metal panels joined in end-to-end relation. Each of the sidewall panels includes a pair of preformed, flange structures along upper and lower edges, and the upper flange structure includes a downwardly and outwardly sloping eave, a reverse turn and an upwardly and inwardly sloping roof segment. The lower flange structure includes a reverse turn, an upwardly extending inside flange and an inwardly extending floor section.The shell includes one or more roof panels having a raised central ridge portion with a pair of downwardly and oppositely outwardly sloping roof sections adjoined along outer opposite edges with the sloping roof segments of the upper sidewall flange structures. One or more floor panels are provided with the opposite outer edges joined to the floor sections of the lower flange structure of the sidewall panel.