Air models allow accounting for air temperature variations within a thermal zone or along the surface of an envelope component. A recently completed ASHRAE research project (RP-1222) produced a source code toolkit focused on coupling airflow models to load routines typical of whole building energy simulation. The two modeling domains are computed separately (and iteratively) with relevant temperature boundary conditions passed back and forth. One of the air models in the toolkit is a new contribution to crude/fast airflow modeling that is based on solving the Euler equation using finite-volume techniques. Computing distributions of air temperatures allows modeling surface convection heat transfer using near-surface air temperatures rather than a single fixed reference temperature. For room airflow modeling, coupling allows moving boundary conditions ”outside” to include weather and thermal storage in envelope materials. For load/energy calculation, coupling allows for air system control based on a ”thermostat” and produces more realistic interior surface temperatures. Examples of applying the coupled program are drawn from current work to design a new thermal test chamber for the Windows Group. The implications of modeling near-wall air temperatures on predicting the condensation resistance of windows will also be discussed.