Soundproofing 1st floor ceiling?

[lumbajac]

Posed a question this past week about soundproofing a bathroom.

Now, how about soundproofing my 1st floor ceiling?

The bedrooms and bathroom are on the second floor... above the living room, dining room, kitchen, office, etc. Am going to insulate below the 2nd floor bathroom for sure and am considering insulating elsewhere as well if time and money permits. I have 9 1/2" deep floor joists. Should I use 4" batts up tight agains the bottom of the floor, 6" batts, or thicker? I'd like to just use the 4" batts for $$$ reasons as this wasn't planned in the budget, but would conside 6's or 8's if that much better and not significantly more cost.

Note - I'm not going to use resilient channels or double layers of drywall or anything like that... not enough time nor $$ for such measures.

Thanks.

 

[Tudorman]

More money will get you better sound control. That's obvious. Put in the most insulation your budget can stand. Then bite the bullet and buy solid core doors if you don't have them already. I did 10" of insulation in my ceilings, along with resilient channels and solid doors. Huge improvement. If I was doing it now, I'd would have used sound deadening drywall. Adds up to big bucks, but the quiet is awesome.

 

[Wet1]

After you put a little insulation in the cavity, adding more doesn't do very much. The best bang for your money would probably be using el cheapo R13. Multiple layers of drywall work well, even if you're not going to decouple them. If you're only going to use a single layer, use 5/8". As TM stated above, solid core doors make a big difference.