Most municipalities in the lower mainland prescribe acoustic requirements for rezoning applications to study outdoor noise ingress and necessary facade improvements to meet interior noise limits such as those mentioned in the CMHC Road and Rail Noise: Effects on Housing criteria. However, there is no standard method of performing this assessment. As there are often no requirements for post-construction testing, the actual interior noise levels are not measured and compared with the initial predictions. After a number of assumptions and theoretical calculations, how accurate are these interior noise predictions?

For a number of residential development projects, we conducted post-construction measurements to measure the actual noise level inside bedrooms. The measurement results were compared with the original predictions to assess the accuracy and identify tendencies to over- or under-predict. In addition, we looked at factors which could influence the accuracy such as facade noise exposure estimate, transmission loss data, and noise ingress calculation. This paper discusses our findings and recommended best practices for interior noise level predictions for Greater Vancouver residential construction.