Marriott Residence Inn Westmount, on Lincoln avenue, is all concrete, even between rooms. About 8' of concrete! If you get the 1 bedroom suite, you have one more door between the action and the corridor. And they have no communicating rooms, removing the "common door" weak point. If you want the ultimate, you take the 2 bedrooms suite and use the bedroom at the end of the hall. Not even somebody walking in the corridor will notice the action!
One time I was staying there, a guest left and forgot to turn the alarm clock off in the room next to me. The beeping was so faint it took me a while to figure-out what it was and where it was coming from!