Abstract: Polymeric bags with pressure relief valves having improved sealing and venting properties are described. Generally, the disclosed bags have opposing body panels connected along a pair of sides, a bottom bridging the sides, reclosable fasteners extending along mouths formed opposite the bottoms, and pressure relief valves attached to one of the body panels. The valves are positioned adjacent a pressure relief opening defined in a body panel of the bag and include a cover member that covers the opening. The cover member includes an upper layer and a lower layer, in which the upper layer is hingedly connected at a first end to the lower layer. The lower layer includes a first portion attached to the body panel and a second contiguous portion not attached to the body panel for relative movement therebetween. The first end of the upper layer is connected to the second portion of the lower layer.