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Air-Infiltration Measurements in Buildings Using Sound Transmission Loss Through Small Apertures

The objective of this investigation is to determine air infiltration in buildings using sound transmission loss (STL) through various types of holes and cracks. The method is based on the use of a sound source that radiates sound waves at a known frequency inside the building and two sound level meters, which measure sound pressure level inside and outside the building. To develop a correlation between STL and air infiltration, experiments have been performed using various types of materials. A test chamber was divided in two sub-chambers to simulate interior and exterior air conditions. Various materials, each with a small hole of varying shapes and sizes, were positioned between the two sub-chambers. A pressure difference has been generated between the sub-chambers and air infiltration in each experiment was measured through each hole. Filed testing in several buildings has been performed to determine air infiltration. The results of field measurements compared with the blower door readings show that the proposed method has promise to be used to measure air infiltration in buildings.