Off peak top venting roof vent

Abstract

A roof vent for an off peak roof location. The roof vent has a base and vent cap. The base includes an attachment flange, a central opening and an upstanding wall surrounding the central opening. The vent cap covers the central opening and has a solid periphery extending down to the attachment flange, and a grill portion located on an outer upwardly facing surface of the cap. A barrier platform is disposed under the grill portion over the central opening to deflect moisture passing through the grill away from the central opening. Vented air passes through the central opening, between the underside of the barrier platform and the attachment flange, between the top side of the barrier platform and the underside of the vent cap and then out through the grill.

We claim: 
     
         1 . A roof vent for an off peak roof location, said roof vent comprising:
 a base including an attachment flange, a central opening to allow the passage of air through the base, and an upstanding wall surrounding the central opening to direct water flowing along the attachment flange around the central opening;   a vent cap covering said central opening, said vent cap including a solid periphery extending down to said attachment flange around the central opening, said vent cap including a grill portion located an outer, upwardly facing surface for allowing air to pass through said cover, the openings of said grill portion defining a net air flow area,   and a barrier platform supported over the central opening between said grill portion and said central opening;   wherein said barrier platform is sized, shaped and positioned to deflect water passing through said grill portion away from said central opening.   
     
     
         2 . The roof vent of  claim 1  wherein said barrier platform defines a lower air gap between the barrier platform and the base and the lower air gap defines an opening at least equal to said net air flow area of said grill portion. 
     
     
         3 . The roof vent of  claim 1  wherein said barrier platform defines an upper air gap between said barrier platform and said vent cap and the upper air gap comprises an opening at least equal to said net air flow area of said grill portion. 
     
     
         4 . The roof vent of  claim 3  wherein the grill portion, the lower air gap and the upper air gap all define a similar net free flow area. 
     
     
         5 . The roof vent of  claim 1  wherein the barrier platform is supported from the vent cap by means of a plurality of suspension members. 
     
     
         6 . The roof vent of  claim 5  wherein said suspension members releasable attach said barrier platform to said vent cap. 
     
     
         7 . The roof vent of  claim 5  wherein there are at least four suspension members. 
     
     
         8 . The roof vent of  claim 1  wherein the barrier platform is supported over the central opening by means of a plurality of support columns extending from said base. 
     
     
         9 . The roof vent of  claim 8  wherein the barrier platform is releasably supported over said central opening by said plurality of support columns. 
     
     
         10 . The roof vent of  claim 5  wherein there are a number of support columns. 
     
     
         11 . The roof vent of  claim 10  wherein said support columns are configured to have a small profile in cross section across the air flow area. 
     
     
         12 . The roof vent of  claim 1  wherein the central opening includes a lower water deflecting rib on all sides to help deflect water away from the central opening. 
     
     
         13 . The roof vent of  claim 1  wherein the barrier platform further includes an upper water deflecting rib on at least three sides to help deflect water away from the central opening. 
     
     
         14 . A roof vent comprising:
 a base including an attachment flange, a central opening through the attachment flange to allow the passage of air through the roof vent, and a lower water deflecting rib adjacent to the central opening;   a vent cap covering said central opening, and attached to said base, said vent cap including side, up slope and downslope walls which all extend down to said attachment flange, said vent cap including a grill portion located on an outer, upwardly facing top surface, said grill portion allowing air to pass through said vent cap and defining a net air flow area, and   a barrier platform supported over the central opening between said grill portion and said central opening to inhibit weather passing directly through said grill portion and said central opening;   wherein said barrier platform is sized and shaped to define a lower air passageway between said base and said barrier platform and an upper air passageway between said barrier platform and said vent cap, each air passageway being sized to be at least equal to said net air flow area.   
     
     
         15 . The roof vent of  claim 1  wherein the lower water deflecting rib extends at least above an upslope edge of said central opening and beside said side slope edges of said central opening. 
     
     
         16 . The roof vent of  claim 2  wherein said side slope lower water deflecting ribs extend past said down slope edge of said central opening. 
     
     
         17 . The roof vent of  claim 2  wherein said lower water deflecting rib extends below said down slope edge of said central opening. 
     
     
         18 . The roof vent of  claim 1  wherein said lower water deflecting rib encircles said central opening. 
     
     
         19 . The roof vent of  claim 1  wherein said down slope wall of said vent cap includes drainage holes to allow water to drain from underneath said vent cap onto said roof 
     
     
         20 . The roof vent of  claim 1  wherein said barrier platform is positioned below said grill portion and has an area at least as large as an area having openings defined by said grill portion. 
     
     
         21 . The roof vent of  claim 1  wherein said barrier platform includes a raised edge to promote water containment. 
     
     
         22 . The roof vent of  claim 7  wherein the raised edge extends along at least some of said side slope edges of said barrier platform. 
     
     
         23 . The roof vent of  claim 8  wherein said upper air passageway is at least partially defined between a top edge of said raised edge and an underside of said vent cap. 
     
     
         24 . The roof vent of  claim 2  wherein said lower air passageway is at least partially defined between a top edge of said water deflecting rib and a lower surface of barrier platform.