A door assembly includes a doorframe, an insulated glazing unit (IGU), door skins, and a gas passageway. The IGU includes a substantially sealed IGU cavity and a hole communicating with the IGU cavity. The door skins are secured to opposite sides of the doorframe and have openings between which the IGU is provided. The gas passageway provides gas communication between the IGU cavity and the atmosphere outside of the door assembly. The gas passageway contains a gas passage conduit that includes a first end communicating with the IGU cavity through the hole and a second end communicating with atmosphere outside of the door assembly. The gas passageway may contain a gas passage conduit having a first end communicating with the IGU cavity through the first hole and a second end communicating with an air pocket, and a channel connects the air pocket with atmosphere outside of the door assembly.