Desiree,
“So the sound, as far as I can tell, is just normal office noise – copy machines, footsteps, loud people.”
OK, here you go.
The idea is to present a barrier of Density-Isolation-Density (D-S-D) to reduce the transfer of vibration.
First, the easy solution. Floor traffic: Carpeting or floor mats on the other side of the wall.
Second, loud people and copy machines. Foam on walls won’t do it. You will get some loss if you foam the office side of the wall, but not enough to do you any good.
You can heavy up the original wall by putting Acoustilead on their side of the wall. Then cover that with a layer of of foam normally used under wall to wall carpet. Then cover that with 5/8″ sheet rock in such a way that the bottom of the sheet rock sits on a lip of lip of excess carpet foam at the bottom of the wall. That way, the sheetrock will be isolated from the floor.
If you need more, construct another sheet rock wall of density and keep it isolated from the original wall. It should be built on the office side to prevent the sound from hitting the original wall. The sill plates should be isolated from the cement floor by rubber mats or Sorbothane pucks. If you drill through the sill plates and into the cement floor to bolt it in, you’ll be conducting sound from your new wall to the floor and under the old wall to your own space. So try rubber gaskets between the bolt heads, the sill plates and the bare floor.
Any questions?
Regards,
Ty Ford
Cow Audio Forum Leader

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