Agreed!

I think the key word is "floating". This isn't a floating floor, it's a naildown. I don't believe it's going to be nearly as effective in a naildown situation, as most of the noise that is "muffled" in a floating situation is from the fact that there isn't good solid contact with the subflooring, as in nailed down. WHen there is good solid contact with a subfloor, the majority of the noise produced is from the reflective (rather than absorbtive) nature of the hardwood surface itself. Sound just echoes more into the air from a hardwood floor than it does from a sound absorbtive carpet floor. No amount of underlayment is going to alter the nature of the sound echo produced because the flooring is a hard floor product and not a textile based flooring product. It may be possible that installing a manufacture approved for naildown installation sound barrier can help with some of the percussive sound transmission from floor to floor, but it'll never be as quiet downstairs as if carpet on padding was the second floor material. And, you'll still get sound echoes upstairs that travel through the walls and open areas, simply because the wood surface reflects sound. You can't alter the basic nature of a hardwood floor. You can use rugs and additional soft furnishings to moderate the sound absorbtive properties and mitigate some of that reflectivity, but you'd have to practically cover all of the rooms wall to wall with rugs to make it be as quiet as carpet could be.

live_wire_oak,

That is irrelevent to the discussion, as Floor Muffler IS approving its use in this application and it's done that way everyday without issue.

The installers job is to make the cuistomers requests happen, not to question a customers purchases based on the installers opinion on it being a pain to isntall or even lying to them about its effectiveness so they have a shorter workday.

Thes installers are lying or inexperienced in the application at hand,a nd either way you slice it, it's a lack of being a professional and I recommend they get someone else.

We have used this product in floaters, glued-down, and nail-down applications without issue.

It simply does not matter that it might be a small percentage less effective because of the anchors. Its a 100% improvement with no product underlayment and much better than comparable products out there that may have equal issue concerning any anchors at all since it is nail down. All product would be less effective with that reasoning, However, if you have data stating otherwise, i would enjoy seeing it.

Floor Muffler is an exceptional choice for this consumers application.

No sound deadening pad installed under any type of flooring is going to affect the sound in the room that is reflected from that flooring. WHat it will do is help to mitigate the percussive transfer of the footsteps that you hear downstairs---which doesn't appear to be the major concern of the poster. "Our concern are the noise when upstairs." That doesn't mean that he won't get a benefit from the product under discussion, it just means that it's not going to correct the major source of his concern, which is the reflective sound properties of a hard surface flooring material.

Agreed that Floor Muffler will not stop in-room reflective sounds within the isntalled space .. the echoey sounds and such as hard surfaces tend to provide. For something like that they would need a sound dampening wall panel, like Armstrong SoundSoak.

By the posters comment, "noises when upstairs", I am assuming he is speaking about sound transfer through the flooring system into the downstairs space, which Floor Muffler certainly will provide dampening properties for.

I would specify it or an equivalent product as a sound attenuating material to use in a solid naildown. But, that said, I would certainly explain to any customer asking for the product to be included in an installation exactly what to expect regards to performance of the product in such a floor system.

The original installers are correct in informing the customer that sound can be transferred via the cleats or staples into the underlying materials. As long as you (the customer) understand that such a product will at best only attenuate noise, I see no reason not to use it.

I suggest you do a search of sound deadening methods in new and existing construction to understand how noise travels in a building and what you must do to reduce its volume. For example, you must make sure that there is a break between your floor surface and any vertical surface. Most flooring is installed with a necessary expansion gap, so that shouldn't be a problem. Just one thing to consider.

The noise we are concerned are those made upstairs and hearing it to the first floor...like children running upstairs & music...
Because there will be an elderly who will stay downstairs.
Having the noise reduction prep needed for the floor is needed.

I looked over the the floor muffler website.

http://www.flooringunderlayments.com/floormuffler.html

And if you read on the "warranty", it only says warranted on floating floors. And yet they have a claim on glued down and nailed down.
There seems to be a conflict.

So is floor muffler really the best option over cork, rubber, foam underlayments available on a nailed down 3/4 solid hardwood flooring on the second floor of the house?

I would love to know the answer to your question. We are debating putting in hardwood above our basement family room. I am afraid.My floor installer said he has used the vinyl under flooring and it does not help at all. I just started researching this, so if I find out anything, I will let you know. PLEASE someone out there answer this, I have wood floors in my kitchen above my furnace room now, and we walked around a lot, and it is definitely noiser then carpet. No type of barrier though, so hoping a barrier will help?