I bought 3/4" solid Brazilian Cherry 3" strips to staple down in my 2nd floor kitchen, entry, and dining room. I have 5/8" plywood subfloor over joists spaced 16" OC. I had naively planned to install over 15# roofing felt, without any additional subflooring or underlayment.

Last night I cut out all my carpet and padding, pulled out tack strips and baseboards, and started to assess the subfloor for flatness. While walking around on the plywood, I was shocked at how loud every step was, even while wearing slippers or barefoot. The problem is the dining room and kitchen are directly above my master bedroom. We checked it and and realized we can hear even soft footsteps of our smallest cat from down below. What's going to happen when our 3 cats have their daily 4am rodeo up there?

Will nailing down something as meaty as 3/4" solid wood reduce the drum-like effect and provide enough mass to muffle the sounds? It was quite good with the carpet and padding. And the old vinyl in the kitchen was still quieter than the bare subfloor.

Before everyone tells me to add another 1/2" layer of plywood to my subfloor, I should tell you that I have done the dishwasher clearance check, and it can go in and out over the 3/4" wood, but it's tight. I might get away with adding 1/8" of height, but nothing more. And yes, the 3/4" wood flooring is already paid for and acclimating in my living room, I can't go back for something thinner.

What things can I do to minimize the noise? Would using 30# felt instead of 15# make any difference? Would a 1/8" layer of cork make a difference?

If I use cork, do I still also use the felt, and which goes down first?

Other suggestions? Any wisdom is appreciated!

Thanks,
Garrett in San Diego

This is why they don't allow hardwood in multi level condos & apartment.
The condo honeowners association has heard complaints and said no more.


It will never be as quiet as carpet and padding, nothing will be, cork or no cork.

A thin cork is going to be a waste of money. To see an noise reduction benefit, your going to need a thick cork underlayment (7/16" - 1/2") and then it is only going to be minimal reduction.


Buy seperate kennels and put the cats in their own little bedroom at night.

Perry:

I appreciate your contributions to the board but you're way off base on this one...



I often thought when I was installing "if I only had a piece of the cork underlayment action" I'd be a rich man In the dozens of condos I worked in since the mid 90's there was almost as much cork underlayment used than there was carpeting. Of course these were higher end condos where stone, tile and hardwood was common.

As far as the original posters question it wouldn't burt to lay some 1/8" thick volara foam down before the hardwood installation. How much it muffles the sound is not within my knowledge but I've heard it suggested before. 16" OC and running the hardwood perpendicular should give it some great strength, unless there are other problems we're not aware of.

I worded it wrong...
I used the word "they", where the word "many" should have been.


Here, there is a law and it has to do with disturbing the peace.

Thanks for the replies.

So Ken, is it your opinion that 1/8" Volara will be more effective than 1/8" cork? Remember, I am stapling the floor down. Does putting something spongy under the flooring have any adverse effects on the installation?

And would the cork or foam replace the asphalt felt, or go on top of it?

Thanks,
Garrett

Hi Garrett,
I helped you before with the layout question. The only purpose the 15 lb. asplhalt felt serves on a SECOND FLOOR above a climatically controlled environment (fancy label for living space with HVAC) is to keep dust down (?) and to allow the flooring to slide easier while being installed. If you have heating ducting running between floor joists (I doubt it) or if your furnace is below the hardwood floor, then the felt will help to retard moisture transfer. That is the main function of the felt. If you are going to use volara foam, I can see no reason to install the felt except to allow the flooring to slide easier and help prevent the foam from being torn. In this case, I would install it on TOP of the foam. Also, I hope your flooring layout and the direction is perpendicular to the floor joists. The flooring should be run 90 degrees to the joists direction; or at 45 degrees at least. If the direction of the joists and the flooring are the same and your subfloor is 5/8" plywood, you should either add blocking between joists (I know this won't happen) OR add 3/8" minimum plywood (1/2" preferred). Since you will probably not be able to do either, at the least, re screw the plywood to the joists to help keep down the squeeks that will be bound to happen IF you run the flooring parallel. Running the flooring at 90 degrees will stiffen things up considerably. Good luck!

I'm looking to solve a similar problem but do not have the same height restrictions and have not bought the flooring yet. This is for a 3rd floor media room / family room and I would like to control as much sound are reasonably possible. I have been reading about a product called sheetblock. It is called a mass loaded vinyl (1/8") and claims to stop more sound than lead. They sell this stuff to recording studios. They recommend a buildup where a sled is created but this would create to much of a height difference with an adjoining room. Owens Corning also has a closed cell foam called quiet floor. I've also heard about good results with using a rubber roof. My joists are 2x10 ( real 2x since it is 100 yrs old) @ 16 and then 1x10 sub-floor.

1) Is mass loaded vinyl or quiet floor any better than cork?
2) should I float the floor using 3/8 plywood and then a 9/16 engineered floor?
3) Should I screw the plywood down or use a T&G product and glue the T&G
4) Should I use a 3/8 hardwood instead?

I'm hoping to find a local installer who has done this before...

Any help is welcome.

OK, I got a lot of conflicting advice on my original question and went with my instinct and ordered 1/8" cork underlayment. While I accept that the noise reduction may be small (due to the 1000s of staples transmitting noise through the cork to the subfloor), I will feel better knowing that I did something with the small height allowance I had. Better than being unhappy with the noise later and wondering if a little cork might have helped.

So here's the question. I've already cut my 15# roofing felt but haven't stapled it down yet. When I get the cork, should I...

(a) loose-lay the cork, lay felt over the top, staple through both, then install wood
(b) staple the felt, staple cork over the top, then install wood
(c) glue the cork, staple felt over the top, then install wood
(d) skip the felt altogether
(e) something else?

I have heard that cork must be glued when used as underlayment for floating floors. I was hoping that wouldn't be necessary with my staple-down (3/4" solid) floor. Can anyone think of possible problems arising from not gluing the cork but just stapling it down?

Thanks,
Garrett in San Diego

What? No fancy diagrams this time? I'm feeling cheated! All kidding aside, I think you'll find the cork is difficult to keep in place without attaching it to the subfloor. If you whack it to death with a hammer tacker you'll most likely damage it. If I where you, I'd lay the cork first and spot attach it just enough to hold it in place and keep it flat. I would then lay my felt over the cork. The only purpose of the felt here is to protect the cork and allow you to slide the flooring more easily. You could delete the felt if you are careful during the install. Whatever you do, felt or no, you'll need the cork flat 'cause you're snapping your layout lines on it. Good luck! For those who don't know; gschiff's floor is on the second floor above a HVAC controlled living space. The felt is not needed as a vapor retarder here.