The house we live in is practically new. The guest bedrooms face the street, and although it's not a super busy one, it does get a fair amount of cars driving by. This drive-by noise is a bit annoying in those bedrooms at night. I'm not sure if the majority of the noise comes through the walls or through the windows, but I have a sense it's actually the windows, which are made by Pella (not that it means much). What can be done to minimize the noise level, without the use of some drastic steps such as tearing down the walls to redo insulation?