An application for a living-hinge air vent valve connectable to a sewer conduit includes a base and a cover sealed to the base forming a cavity between the cover and the base. A fluid inlet shaft depends from a roof of the base and is connected to external air passages passing through a side of the base and through vents in a side of the cover. A living-hinge flapper is situated above the fluid inlet shaft and within the cavity. The living-hinge flapper allows air to flow from the fluid inlet shaft into the cavity and prevents sewerage gasses from flowing from the cavity out through the fluid inlet shaft. One or more connecting shafts in the base fluidly connect the cavity with a sewer system.