Nonmetallic vent with integral screen

Claim 1

A nonmetallic vent comprising, in combination, an elongated nonmetallic base of generally rectangular configuration having spaced lateral sidewalls interconnected by end walls, a top panel and an open bottom, a peripheral flange extending outwardly from said walls at said open bottom, said top panel consisting of a plurality of spaced, parallel, elongated first elements homogeneously extending from and between said sidewalls and a plurality of spaced, parallel, elongated second elements homogeneously extending from and between said end walls intersecting said first elements, and openings defined intermediate adjacent first and second elements, respectively, wherein said top panel comprises an open grid screen, a nonmetallic cover of an inverted dish configuration having a cover panel and a downwardly depending peripheral wall including side portions and end portions, said end portions closely overlapping said said base end walls adjacent said base top panel, said cover end portions each including a lower edge, a cover supporting ledge defined on each of said base end walls spaced below said top panel and above said flange, said cover end portions lower edges each engaging one of said ledges, fasteners interconnecting said overlapping end portions and end walls mounting said cover on said base with said cover panel in spaced relation to said top panel, said cover side portions being spaced apart a greater distance than said base side walls and overlying said sidewalls and top panel venting said top panel screen.