Increasing trends toward urbanization can lead to increased exposure to transportation noise from automobiles and aircraft. Interestingly, current aircraft noise guidelines primarily are based on outdoor sound levels even though most people spend the majority of their time indoors. A research project is being conducted that provides insight into how typical residential envelopes affect indoor sound levels, with a focus on noise from commercial aircraft overflights. A pilot, single-room "test house" has been built using typical mixed-humid climate region construction techniques, and the outdoor-to-indoor transmission of sound is being directly measured. The test house results are being used to validate and improve computer models that can be used to simulate outdoor-to-indoor transmission of sound. These models will allow for flexibility in future work to simulate a wide range of construction types for other U.S. climate regions, as well as effects of acoustic and energy retrofits. The improved models developed through this project, therefore, will help improve understanding of expected acoustic performance for typical construction types around the United States including design alterations that can help insulate homes from aircraft noise.