Hey guys-
Just got a quote back from an insulation company and they're wanting to insulate between the upper and lower floor of our house for sound deadening.
I'm curious as to how much this would really help, as I thought the sound was transmitted mostly through the framing?
Any one have an opinion on such things?
I'm pretty knowledgable as far as DIY guys go.
There are two types of noises, the kind that you hear with footsteps and bangs, and the kind that is talking or music. Regular ol insulation does actually help considerably with the voice/music type of sound. It's pretty much the best bang for your buck there is in regards to that.
Footsteps and impact noise is indeed transmitted through the materials. Insulation will do little to nothing in regards to these.
You are unlikely to prevent this without doing things like decoupling the layers and/or adding mass. But decoupling and adding mass will prevent sound transmission from all sources effectively. It's also expensive.
People always want to go overboard in this area, but I think there are some reasonable things you can do on a budget.
-use a heavy/thick pad if your going with carpet or floating, it won't cost much more.
-hardwood, use real 3/4" thick wood
-If you're tiling, use cement board. 1/2" cement board + tile = quiet
-Use 5/8th's firerock for your ceiling, just for the mass, and it's cheap.
-Make sure all points are caulked/sealed well, nothing will transmit noise better than openings between the two places.
I could go on for awhile in the different types of noises, frequencies, and how to prevent them, but sticking to the basics is usually a much better bang for your buck if you just want to live peacefully and don't have a specific reason for blocking out sound (ie home theatre below your childs bedroom)