

I did not think to take "during" photos, so you'll have to just trust me on this one. In order to improve sound control on this wall, we installed sound control insulation between the existing studs. I then drywalled, taped and mudded the wall. Finally, I framed a new 2x4 wall on our side of this drywall.
When we're ready to finish the room, we will install more sound control insulation between these studs, and then install drywall. Who knows how much quieter this room will be, but at a cost of 4" of space, $50 of materials, and 2 hours of time, it was worth a try.
I didn't notice until after reading the article that this was written back in 2005, which is interesting because I had not heard of some of these concepts before (e.g. header hangers). I don't know if all of these framing techniques are permissible by code (not even sure of a good place to look up code requirements in Ontario?), but the argument for better energy efficiency is convincing.