[Master Brian]

I am wanting to insulate the floor space between my main floor and basement for sound isolation.

It seems when I google this, I find 1/2" sheets of this or that. I'm not crazy about this for two reasons. 1st, I don't want to drop the ceiling another 1/2" or more and 2nd, the cost seems to get kind of high.

My main goal is just to cut the sound down. I am finishing the basement for a TV/game room and there are bedrooms and a kitchen above this area. I have 2 young girls and I don't want to wake them at night if I watch a movie and I don't want them to disturb the rest of the house if they are downstairs playing. I think you get the idea.

My initial plan was to just install 6" thick fiberglass batting to the floor joists and cover with sheetrock. The little bits I have done, does help, but someone mentioned this isn't a great sound proofing technique. What are some cost effective ideas?

Should I double up the batting in the joist bays, so that it is really dense?

I am having fur out the bottom of the joists with 2x4's to get around things like my a/c line, some plumbing, etc. What about installing some 1-1/2" rigid foam between the 2x4's. So basically, I'd have 6" thick batting in the joists, and rigid foam under.

Thanks for any ideas/suggestions....

 

[Just Bill]

Basic insulation does not do a lot to block sound, although it does help some. Real sound insulation is expensive. Do a search for sound deadening and you will find a variety of ways to reduce sound travel, none are easy or inexpensive.

 

[Mike Swearingen]

I understand that "mineral wool" is an excellent sound-deadener, as well as being fireproof. I have no idea what it costs, but it may be something that you can at least check out.
Good Luck!
Mike

 

[Master Brian]

Maybe I'll just have to live with the little bits of help, I gain from batting, which is fairly good. The mineral wool doesn't look to be inexpensive and this isn't that important to where I want to spend $$$ to get the sound down.

I do kind of wonder if blowing cellulose in would be any better. Cost wise, it probably wouldn't be much more than the batting, it would be a bit more work and mess. Hmmm....

The crappy part of this is that my in-laws had a business doing some of this stuff until just a few years ago. When they closed the doors, they probably threw out tons of stuff that would have worked.....

 

[Gary in WA]

I vote for the mineral wool.

http://books.google.com/books?id=VL...X&oi=book_result&ct=result&resnum=8#PPA137,M1

http://www.gp.com/BUILD/product.aspx?pid=1071

Be safe, G