An inflatable dunnage bag for filling empty space within a container is provided. The inflatable dunnage bag includes a bag portion and a valve assembly. The valve assembly is connected to the bag portion and defines a passageway through which a fluid is introduced into the bag portion during an inflation process. The valve assembly may include a backing plate, a flap, a projection, or combination thereof. The backing plate may be positioned between front and back walls of the valve assembly and be configured to protect the back wall from an inflation nozzle inserted through the front wall during the inflation process. The backing plate may include a flap adapted to further protect the back wall and help direct the fluid flow toward the bag portion. The projection, such as a hook, is configured to position the valve assembly to a predetermined area of the container.