Have a LR floor, bare now, plywood over wood joists, have access to both sides (above and below). While it will get carpet of some sort as a top layer, I have the opportunity to do something now to attenuate foot fall noise, and other higher frequency noise that might be transmitted through the floor to the space below.
The key thing is that whatever is used can't be "mega bucks". It needs to be effective and not to crazy difficult to apply.
My immediate thought is to acquire some ~1/8" relatively soft rubber sheet and apply to the floor with 1/4" or 3/8" plywood over, held in place by screws that are set recessed slightly in predrilled holes (spaced in a pattern - just to keep the sheets from ever shifting), so the plywood "floats" on the rubber.
The advantage to this idea is that it can be removed without much effort later - need be. Or if it proves not effective enough.
The other method I've seen mentioned commercially is two layers of plywood that are bonded together by an elastomer. But I don't know where to start with getting a suitable elastomer - the commercial products are imo, way overpriced.
There are all sorts of 5 gal pails of elastomeric roof coatings out there, but which one??
Things like "Liquid Nails" do not stay compliant past a short period of time, and will not be happy under compression for this application. Something that rolls or sprays on might be good - but it needs to be thick enough to be effective.
A layer of "ice guard" material (for roofing) would no doubt be super, but I don't know if it outgasses, or has a petroleum component.
I *CAN* apply or spay things below the floor between and on the joists. Or do both above and below.
So, the question is what are proven materials and techniques that might be applicable here?
The goal is absolute maximum dB attenuation from LF to HF of the top floor surface through the ceiling above the room below.
Consideration can be given to getting more attenuation from the ceiling system that is below the LR floor. But the main focus needs
to be on the floor surface first - I can attack the underside after the floor above is finished.
Ask questions, as needed!
The key thing is that whatever is used can't be "mega bucks". It needs to be effective and not to crazy difficult to apply.
My immediate thought is to acquire some ~1/8" relatively soft rubber sheet and apply to the floor with 1/4" or 3/8" plywood over, held in place by screws that are set recessed slightly in predrilled holes (spaced in a pattern - just to keep the sheets from ever shifting), so the plywood "floats" on the rubber.
The advantage to this idea is that it can be removed without much effort later - need be. Or if it proves not effective enough.
The other method I've seen mentioned commercially is two layers of plywood that are bonded together by an elastomer. But I don't know where to start with getting a suitable elastomer - the commercial products are imo, way overpriced.
There are all sorts of 5 gal pails of elastomeric roof coatings out there, but which one??
Things like "Liquid Nails" do not stay compliant past a short period of time, and will not be happy under compression for this application. Something that rolls or sprays on might be good - but it needs to be thick enough to be effective.
A layer of "ice guard" material (for roofing) would no doubt be super, but I don't know if it outgasses, or has a petroleum component.
I *CAN* apply or spay things below the floor between and on the joists. Or do both above and below.
So, the question is what are proven materials and techniques that might be applicable here?
The goal is absolute maximum dB attenuation from LF to HF of the top floor surface through the ceiling above the room below.
Consideration can be given to getting more attenuation from the ceiling system that is below the LR floor. But the main focus needs
to be on the floor surface first - I can attack the underside after the floor above is finished.
Ask questions, as needed!
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You know, I bet we don't go to Home Depot and ask about speakers, but why not go to a flooring company/retailer or even the aforementioned Home Depot (Lowes, Menards, whatever) and ask for advice?
I could probably think up some materials and ways to apply them, but this is not the first time your need has come up, at least to the flooring industry.
And if you want to get REAL specific, the recording industry has been fighting this fight for decades. Find some recording forums to ask in. A quick google found this for me:
The Acoustics Forum Forum
Note the very first sticky topic in that forum.
Also:
https://www.gearslutz.com/board/studio-building-acoustics/
I could probably think up some materials and ways to apply them, but this is not the first time your need has come up, at least to the flooring industry.
And if you want to get REAL specific, the recording industry has been fighting this fight for decades. Find some recording forums to ask in. A quick google found this for me:
The Acoustics Forum Forum
Note the very first sticky topic in that forum.
Also:
https://www.gearslutz.com/board/studio-building-acoustics/
Yeah... I'll look at the two forums...
The people at the big box stores are essentially ignorant.
This is not a simple question, one that they will not really know anything about.
I'm hoping someone here has specific experience with specific techniques and materials.
I have the Alton Everest book, fwiw.
_-_-bear
The people at the big box stores are essentially ignorant.
This is not a simple question, one that they will not really know anything about.
I'm hoping someone here has specific experience with specific techniques and materials.
I have the Alton Everest book, fwiw.
_-_-bear
The Acoustics Forum Forum topic has good info, but I can't do a high mass floating floor.
🙁
I'll look into the gearslutz thread for specific ideas that might apply...
🙁
I'll look into the gearslutz thread for specific ideas that might apply...
You put 2" or more of vermiculite in between the floor joists. Cheap and more effective that just about anything else. Keeps railroad noise out of recording studios. Costs about $1 per square foot.
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those techniques are well known and rated on STC scale.
good soundproofing which includes low frequencies and structure-borne sound is not simple and it costs big $$s. decoupling two sides of the wall/ceiling by giving them separate studs/joists, using resilient channels for mounting thicker drywall (mass loading springs) etc.etc... it's all out on the net. in Japan they even support complete floor frames with hydraulic mounts (like engines are supported in the cars). just using an elastomeric sheet like duracoustic or similar has a limited effect. also look up mass loaded vynil barrier and make sure you seal any gaps! good luck.
good soundproofing which includes low frequencies and structure-borne sound is not simple and it costs big $$s. decoupling two sides of the wall/ceiling by giving them separate studs/joists, using resilient channels for mounting thicker drywall (mass loading springs) etc.etc... it's all out on the net. in Japan they even support complete floor frames with hydraulic mounts (like engines are supported in the cars). just using an elastomeric sheet like duracoustic or similar has a limited effect. also look up mass loaded vynil barrier and make sure you seal any gaps! good luck.
If it's just footfall and high frequency noise, make sure the floorboards are screwed securely to the joists. And make sure the joists are even and secure. Line the gaps between joists with rockwool or similar insulation. Works well for heat as well as noise.
If it's bass transmission you want to reduce then that's a lot more work.
If it's bass transmission you want to reduce then that's a lot more work.
footfall is impulse + bass.
rockwool will have very limited benefit, unfortunately.
I'm intrigued by the vermiculite solution... my elastomer idea was to damp the impulse and reduce the amplitude that is transmitted.
There is no need to float the floor, etc, since this space is a basement, and the goal is merely to limit the sounds *above* from coming down, attenuation UP is the bonus. 😀
_-_-
rockwool will have very limited benefit, unfortunately.
I'm intrigued by the vermiculite solution... my elastomer idea was to damp the impulse and reduce the amplitude that is transmitted.
There is no need to float the floor, etc, since this space is a basement, and the goal is merely to limit the sounds *above* from coming down, attenuation UP is the bonus. 😀
_-_-
the Green Glue site had some good looking info
carpet pad and/or floating flooring would help - carpet pad can improve/reduce reverberant noise in the upper room too
spring suspended, resilient channel or independently framed ceiling below is a way to avoid the mechanical short circuit of the solid wood path of same joist supporting floor above and ceiling below
https://www.google.com/#q=soundproofing+resilient
some sound proof walls use completely separate studs for each face that don't touch the opposite wallboard
I believe I've seen warnings that just treating directly above may not help as much as expected - the solid wood path of joists conducts foot strike noise from quite a ways, rooms away
that's why the suspended, mechanically isolated walls and ceiling "room within a room" construction is recommended enclosing the quiet/isolated space
carpet pad and/or floating flooring would help - carpet pad can improve/reduce reverberant noise in the upper room too
spring suspended, resilient channel or independently framed ceiling below is a way to avoid the mechanical short circuit of the solid wood path of same joist supporting floor above and ceiling below
https://www.google.com/#q=soundproofing+resilient
some sound proof walls use completely separate studs for each face that don't touch the opposite wallboard
I believe I've seen warnings that just treating directly above may not help as much as expected - the solid wood path of joists conducts foot strike noise from quite a ways, rooms away
that's why the suspended, mechanically isolated walls and ceiling "room within a room" construction is recommended enclosing the quiet/isolated space
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I have the same issue to work on, here. Through some investigation I've found that, in my case, the worst offender is the GFA HVAC system shared between floors. You can do all you want to the floors and walls, but heating ducts will pass the sound right on through. So, I'm looking at ways to minimize that (considering removing the ducts in the listening area and using radiant electric heat for that room only).
http://www.soundproofingcompany.com/soundproofing101/the-dead-vent/
currently takes forever to load anything from them, nearly gave up - surf for a while, come back
currently takes forever to load anything from them, nearly gave up - surf for a while, come back
Put a Low Pass helmholtz (if possible) between the duct and the exit vent.
That looks often like the same sort of construction as a car muffler...
or so I have read...
Yes, I am concerned about the transmission via the floor joists.
There is not much height in the basement space, so hanging a sprung ceiling is going
to be trick.
Again, cheaper is mo' bettah...
No opportunity for "room within a room" type solutions.
A thin layer of fine sand with ply over, and then carpet +/- felt/foam is also a consideration...
That looks often like the same sort of construction as a car muffler...
or so I have read...
Yes, I am concerned about the transmission via the floor joists.
There is not much height in the basement space, so hanging a sprung ceiling is going
to be trick.
Again, cheaper is mo' bettah...
No opportunity for "room within a room" type solutions.
A thin layer of fine sand with ply over, and then carpet +/- felt/foam is also a consideration...
Mass loaded vinyl
You could try with mass loaded vinyl sheets. It's good for both high and low frequencies.
Acoustiblock is one such product and here's a link with different ways of mounting: Acoustiblok suggested installation methods
You could try with mass loaded vinyl sheets. It's good for both high and low frequencies.
Acoustiblock is one such product and here's a link with different ways of mounting: Acoustiblok suggested installation methods
Sand is the best if the floor can take the weight. Next is vermiculite. Carpeting is intended to reduce the initial impulse. It provides little loss. Mass has loss but loose fill not only has mass the motion converts LF to HF which is more easily attenuated. Floating floors, elastomers etc are trying to decouple the floor, that way the 20 db you get from the floor and ceiling actually add up to 40 db, coupled they would be 26 db typical.
Vermiculite starts at 40 db for 4" from 40 hz up.
Vermiculite starts at 40 db for 4" from 40 hz up.
Ed, how do you propose to hold the vermiculite fill below the floor and between the joists? And is there any requirement/benefit to having the vermiculite fill in mechanical contact with the floor above.
The sand would be above the existing floor, and in a thin sandwich with some ply above...
...thinking I can use a handful of compressible spacers per 4 x8 ply sheet to maintain the proper spacing, keeping the sand in contact with the upper sheet of ply.
_-_-
The tentative plan at the moment is thin sand layer above, vermiculite below...
The sand would be above the existing floor, and in a thin sandwich with some ply above...
...thinking I can use a handful of compressible spacers per 4 x8 ply sheet to maintain the proper spacing, keeping the sand in contact with the upper sheet of ply.
_-_-
The tentative plan at the moment is thin sand layer above, vermiculite below...
I would use 1/2" drywall to the existing joists. Use 1 1/2" drywall screws with threads for wood. Fire code may even require thicker. Be sure there are no gaps. A 1" hole in a 45 db wall can reduce it to 12 db. Tape and spackle the joints. A two person job putting up the drywall, but not very hard.
A uniform covering of the fill is best, no it does not need to have contact with the floor above. It is a barrier.
Over here, sound isolation between floor/ceiling, is usually done by fiberglass insulation between the joists, - at least 8'', and the ceiling below has to be clad, somehow... drywall type is usually OK. Then a secondary framework, 2x2 or 2x3 is hung on small metal brackets, and another lower ceiling, at least one layer of gypsum or drywall type or similar is hung on the secondary framing... Another system used over here is very hard rockwool plates, appx 3/4'' laid on the existing floor, and then another floor layer on top, - ply, hardwood etc.etc.this is the type of brackets used...
Surely some of these solutions must be available in the US..??
This is a pic of the brackets used for the sub-ceiling
Surely some of these solutions must be available in the US..??
This is a pic of the brackets used for the sub-ceiling
Attachments
That bracket (a spring system) is to hold UP a floor, or to suspend a ceiling?
I'm unclear on what sort of "hard rockwool plates" those might be? are they load bearing or just a hard rockwool material used between surfaces?
Here in the US Dow Corning, amongst others make a wall system (often sold for basements and offices) that is a hard rockwool or fiberglass sheet available with an architectural (fabric usually) finish. The 4" has pretty decent attenuation characteristics, but it is not inexpensive material.
So, Ed, the idea is to put drywall between the joists, or under the joists as the ceiling?? I'd expect that such a direct connection to the joists might make a decent path for direct sound, despite the general attenuation of the vermiculite??
Thinking out loud, maybe a plastic sheet to go across the joists, prior to the installation of the ceiling, to hold the vermiculite and to be able to visually assure a good fill??
The installation of the vermiculite would be how? Blown??
I'm unclear on what sort of "hard rockwool plates" those might be? are they load bearing or just a hard rockwool material used between surfaces?
Here in the US Dow Corning, amongst others make a wall system (often sold for basements and offices) that is a hard rockwool or fiberglass sheet available with an architectural (fabric usually) finish. The 4" has pretty decent attenuation characteristics, but it is not inexpensive material.
So, Ed, the idea is to put drywall between the joists, or under the joists as the ceiling?? I'd expect that such a direct connection to the joists might make a decent path for direct sound, despite the general attenuation of the vermiculite??
Thinking out loud, maybe a plastic sheet to go across the joists, prior to the installation of the ceiling, to hold the vermiculite and to be able to visually assure a good fill??
The installation of the vermiculite would be how? Blown??
Drywall covers the bottom of the joists normal floor style. Even the energy transmitted through the joists must try to move the drywall and the filling absorbs that.
Fiber glass has very low transmission loss particularly at low frequencies.
A decoupled second ceiling will yield 25-35 dB of additional loss if done perfectly. More reasonable is 15 dB.
If you want a bit of decoupling use bits of carpet padding between the drywall and the joists just where you place the mounting screws.
Normally the vermiculite is dropped in from above before the floor is finished. I would put it in bags and tack them up overlapping a bit.
Fiber glass has very low transmission loss particularly at low frequencies.
A decoupled second ceiling will yield 25-35 dB of additional loss if done perfectly. More reasonable is 15 dB.
If you want a bit of decoupling use bits of carpet padding between the drywall and the joists just where you place the mounting screws.
Normally the vermiculite is dropped in from above before the floor is finished. I would put it in bags and tack them up overlapping a bit.
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