Replace plaster for better soundproofing

Hello again,
I have been asked to convert an office in a building that is our local birth center. This is where local folks can go if they are using a midwife and would like to have a few more amenities than just delivering at home. The owners of the birth center are getting nervous about all the births they anticipate in the future (like our second child due in July:) ) and want to convert an office to another birthing room. The room in question shares a wall with the waiting room. They are asking about the possibility of adding soundproofing to that wall. My initial thought was to strip one side of the wall down to the studs and add some combination of insulation, rubber, soundproof drywall etc (more research needed). Both sides of the wall have the original lathe and plaster intact, in very good condition. So the question is: how good of a job does lathe and plaster do as soundproofing? I don’t want to go to the effort of tearing out the plaster and engineering a potentially expensive soundwall only to find that in fact lathe and plaster does a pretty good job already. Any thoughts?
Replies
Is it wood lath strips or gypsum lath? I would think those old plaster walls would be dense enough to block alot of sound. One quick test would to put a radio on one side and see how loud you have it turned up before you hear it.(or put a "birthing mom" in there and see what you hear)
I'd leave the wall and construct another soundproofed wall next to it so you have a double wall. (Don't wanna scare off the customers!)
Mike Hennessy
Pittsburgh, PA