# Soundproofing Question



## wetech (Aug 4, 2012)

You'll probably be fine with the 3" of roxul. Maybe add some horizontal strapping to one or both sides using resilient channel (usually used for basement ceilings) and attach your drywall to that.


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## ZTMAN (Feb 19, 2015)

Two layers of drywall in addition to the insulation, otherwise your studs will transmit the sound


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## mako1 (Jan 7, 2014)

I would go with the roxul plus 2 layers of 5/8" drywall and some of this :http://www.greengluecompany.com/products/noiseproofing-sealant
There is also sound proffing drywall available.


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## Nestor_Kelebay (Jun 17, 2008)

Also maybe check out Owens Corning "Quiet Zone" soundproofing products.


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## Hick (Nov 21, 2014)

Understand what sound is, it is the vibration of air.

Simplest solution is remove the air. Remove the air, you remove the problem. However, in practice, creating a vacuum in your wall is going to be challenging to say the least. Even with a vacuum, your walls will still vibrate the sound from one side to the other through sheetrock & studs. Kinda like a Newton's Cradle.

There is also flanking noise to consider. You can dead the wall all you want. However, sound will still enter by going under your floors or your attic or even around the wall. Particularly through windows. 

So, basically filling the void. The denser the material the better, it removes the air. Another is reflection. Sound bounces. I would assume placing some shims behind the middle part of your drywall to give a slight bow to the outer edges will help redirect the sound from going straight through.

I have seen egg cartons used to fairly good effect for cheap soundproofing. You could attempt this route by stapling them to the inside of your drywall before hanging it to help the sound bounce & give it a cavity to get trapped in.

There is also staggering your studs. You can also put more layers ontop of your existing wall. Something like thick planks of wood on your walls will help deaden the noise.

Many things to do but its going to boil down to removing air & reflection.


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## Windows on Wash (Aug 30, 2011)

Filling the void is correct but if you are trying to build a truly soundproof system, you have to address the framing as you mention in your second to last paragraph.


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## Hick (Nov 21, 2014)

Windows on Wash said:


> Filling the void is correct but if you are trying to build a truly soundproof system, you have to address the framing as you mention in your second to last paragraph.


Of course, as mentioned sound is a vibration of air(actually all vibrational mediums but for our purposes....air). That is simply all sound is. Remove the air and/or the vibration will remove the sound. Preferably both. 

Do that & you have sound proofing, though a room devoid of atmosphere doesn't make it habitable but it does make it sound proof. 

As they say, in space no one can hear you scream, due to sound not having a medium with which to travel through.


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