The really important thing to know, Timkin, is that the expressway was already there when it was built. OK, not as high on the building as it is now, but it was there, and we built it anyway. And guess what? We never heard the expressway when we were inside the building working. I guess they put in windows that kept the sound down, yes, even in 1973. Hmmm....wonder if you would hear it in a condo across the way, with what must be even better sound-deadening windows in 2013? Probably not. :-)
But there I go again, after I asked not once, but twice, to move this discussion, going off on the PS#4 tangent with you. LOL