Sound dampening insulation/material help! (floor joists)

My wife and I added a second floor to our home, I managed to build an extra bedroom over a room in my carport that will eventually be semi enclosed as a mudroom.
The room above the mudroom is my 2 year old daughters bedroom.
I have noticed that a lot of noise/sound gets through the floor, and that is not acceptable.
I had 5" of polyurethane (R34) foam sprayed in to the 2X10 floor joists leaving me about 4" to work with.
I need to find a material that will dampen the sound travelling through my daughters bedroom floor from the carport/mudroom before I drywall it, and could really use some suggestions!
Thanks

They sell stuff for cars to dampen the noise -- it comes in bats to go inside doors, under the hood, etc. But it's been so many years that I can't think of the name of the stuff!

jus found the following for you, hope the info helps



soundproof foam

explaination ...

lastly ....

Sound insulation or dampening sound is complex.
Mass is the best solution. The more mass at the side where the sound is made the better. Can you get sound insulation board? You could attach that to the ceiling and put as much insulation material in between the boards and floor of your daughter's room.

Maybe a stupid question, but I like asking stupid questions : what is causing the sound? Your car or machinery as well? What kind of floor does your garage have, concrete? If it is a hard floor like concrete, you could use a softer material over the hard floor. Two layers: Cork or rubber with a finish layer over it. That way the sound won't bounce that much to the ceiling.

any help?

Lots of help, the floor is patio slabs, it was exterior until this year. The noise that is passing through is the back door opening (visible in photo), people talking, the other two kids playing..
I was really counting on that spray foam to help, but not even close..

The door opening is an invitation to the sound to go through. Better is to close it. Is it double glazed?

Patio slabs, so a hard floor. Any sound will bounce from it.
Any windows? Curtains absorb well. The more material the better.

Sound might be coming in more places than are obvious. In our house, exterior sound was coming into the second floor bedrooms through not only the windows, but through the attic. 3 ft of fiberglass insulation and an IR barrier helped quite a bit with noise and heat management.

At a minimum, adding a layer of plywood or OSB to the ceiling will help.

I assume the interior is already carpeted, but if not, consider to add a really heavy pad - something like 10 lb rated pad - big difference. It might even be worth puling the carpet back up to put a heavy pad down.

Caulking can help sometimes.

Before you drywall use sound isolation clips on the studs. They reduce the amount of energy that travels throught the studs onto the next room. Also, use two sheets of drywall with air gaps between the drywall(1/4 inch wood strips to create air gaps). This is a cheap and easy way to reduce the amount coming through the drywall.

Check the Dynamat website http://www.dynamat.com/index.html under the home section they make a roll product to attach to walls/ceilings that you can drywall over. A room over a garage is tough for 1 reason the garage behaves like a huge Bass speaker due to its size and cement floor. dynamat also makes a spray sound-deadener but not sure if you want to spray over the foam again the roll product seems like the better option to me.

Carpet in the room above will help a lot I believe. Standard insulation is not good at sound dampening. I once had a former CEO of Owens-Corning insulation visit me and he said insulation tests found no appreciable sound deadening effects unless you have at least a 2 foot thick wall filled with insulation.

You need some Safe 'n Sound then some Z-furring channel and finish it with drywall.

Thanks for the advice guys, I am going to look in to each suggestion, finishing this room is getting close to being on top of my to-do list.

Hey pydpiper, would you post some info on how the project turned out and what worked/didn't work? I have to soundproof a basement.

When we divided one office into two at our church we offset the studs. The reasoning was so that the opposing sheets of drywall weren't attached to a common stud. Sound (vibration) travels from one room to the adjoining through the studs and drywall. Think about when you put a water glass on a wall to hear what's being said in the next room. Installing a suspended ceiling might be an option.

~ Chance

TTK


Edit I just noticed the op date.