Flow measurements using rracer gas reclmiques were made on tile exterior doorway of a test house for indoor-outdoor temperature differetJces of 0.5-45 K. The time for door opening and closing was constant at 3.75 s, and fully open hold time varied from 0.5 s to 120 s. Predictions of a variable density sready flow model were in good agreement with the measurements when adjustmenrs were made for the time-varying size of the opening and for the effect of cross-stream mixing between the incoming and outgoing air streams.