I like baby monitors for their one-way-ness. If I just open a door a bit, I can hear a baby just fine, but the baby can also hear me. Would you believe that babies can get woken up by their parents making noises?
I think we gave up trying to be quiet around our baby after the first few weeks. Sooner or later a postal delivery will drop heavy-items through the door, just as the baby is trying to sleep, or some other random noise will occur.
I know all babies are somewhat different, but at least ours seems to be happy to sleep through most noises - up to and including using a vacuum-cleaner in the next room.
I try to keep things a little quieter than usual around bed/nap-times, but otherwise the family life must go on. If the baby wakes up sometimes because you boiled a kettle, dropped a book, or turned on the laundry then that's just something you have to deal with at the time.