Polymeric bag includes first and second opposing body panels attached to each other along a pair of opposing sides and a bottom bridging the sides, a reclosable fastener extending along a mouth formed opposite the bottom, a pressure relief opening defined in the first body panel, and a pressure relief valve attached to the first body panel. The valve includes a cover member to cover the opening. The cover member includes an upper layer and a lower layer, the lower layer including a first portion attached to the body panel and a second portion contiguous with the first portion but not attached to the body panel. The upper layer has a first end hingedly connected to the second portion of the lower layer on a first side of the pressure relief opening, and the upper layer has a second end fixedly attached on a second side of the pressure relief opening opposite the first side with the upper layer covering the pressure relief opening. An additional aspect includes a seal line extending proximate the pressure relief opening.