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interior 2 x 4 wall insulation

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interior 2 x 4 wall insulation (post #192641)

geoman on Fri, 08/20/2010 - 08:52
in

Hi Everyone,

I want to install interior wall insulation for sound quieting purposes.  One of the interior walls separates a bath jet tub from our new kitchen.  I bought kraft faced R-13 insulation for everything, both exterior and interior walls.  Someone at the building supply store said it's not a good idea to use kraft faced insulation on interior walls because the wall needs to "breathe".  A friend said that an insulation supply house he frequents sells a sound deadening insulation that is supposed to be far superior to regular fiberglass batt insulation.  I would like to go to town and just use my kraft faced material (Owens Corning Pink Kraft Faced) throughout.  Am I committing a sin and would I be well advised to spend extra money on a product that is supposely superior in limiting acoustic transmission.


Many thanks again!

GEO

-A +A

I don't think there is (post #192641, reply #2 of 19)

by Scott in reply to geoman [original] on Fri, 08/20/2010 - 10:28

I don't think there is anything technically wrong with your choice of insulation, but I think there may be better materials to deaden sound. Around here it's common to put two or three layers of drywall between studs.

Another option might be to widen the wall by adding staggered 2 x 4 studs (offset from the original studs) so that there is no acoustical bridging.

You don't need to worry about (post #192641, reply #1 of 19)

by xxPaulCPxx in reply to geoman [original] on Fri, 08/20/2010 - 10:27

You don't need to worry about it on the interior walls.  What is on your outside walls?  Is this part of a bathroom remodel?

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I think you missed his point. (post #192641, reply #5 of 19)

by Clewless1 in reply to xxPaulCPxx [original] on Sat, 08/21/2010 - 06:35

I think you missed his point.

There ain't NO free lunch. Not no how, not no where!

Really should be no problems (post #192641, reply #3 of 19)

by JohnFinn in reply to geoman [original] on Fri, 08/20/2010 - 13:41

Really should be no problems using what you have on hand, it will help.

However, if you haven't hung gyp board yet consider sound deadening board.

There is better stuff for (post #192641, reply #4 of 19)

by DanH in reply to geoman [original] on Fri, 08/20/2010 - 15:15

There is better stuff for sound control, but the craft facing won't hurt anything, and will probably slightly help with the sound control.


We are like tenant farmers chopping down the fence around our house for fuel when we should be using Nature's inexhaustible sources of energy -- sun, wind and tide. ... I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that. --Thomas Edison

There are better materials (post #192641, reply #6 of 19)

by Clewless1 in reply to geoman [original] on Sat, 08/21/2010 - 06:40

There are better materials used for sound insulation. So it depends on how critical the issue of sound is for you. Filling a cavity w/ insulation may not be as good as a partial fill (I think).

Another couple of options:  two layers of drywall on one or both sides. Hat channel and drywall ... the standard for sound deadening ... or maybe the poor mans approach by using 1 x strapping and then the drywall.

In addition to insulation, sound is controlled by 1) mass (e.g. drywall) and 2) physical separation of structure that transfers sound.

Try to isolate the mechanics of the tub jet system to minimize the transfer of sound through physical contact.

There ain't NO free lunch. Not no how, not no where!

sound proofing (post #192641, reply #7 of 19)

by k1c in reply to geoman [original] on Sat, 08/21/2010 - 11:17

Sorry I forgot the name, but something called ....wool insulation which are usually used as fire blocks, also work better than fiber insulation for sound.  The fire block insulation is denser.  Extra layer of sheetrock will definitely help.  If you want to cut the noise completely, that is a different story.  FHB did a article about it and should come up in the search.

I think motorized tub would be difficult to sound proof since it sits in contact with the structure.  You can add more insulation under the tub flanges or spaces too but tub motor will need some space to keep cool.  Hope it helps.

Any light, fluffy insulation (post #192641, reply #8 of 19)

by TedWhite in reply to geoman [original] on Wed, 08/25/2010 - 10:09

Any light, fluffy insulation will do the job. There's no lab data that demonstrates the expensive stuff works any better than the inexpensive.

Paper faced is fine. I like it because it's convenient to staple to the studs.

You could double up on the drywall, but the motor from the whirlpool will likely be introducing a lot of vibration into the floor. This is considered impact noise and will not be lessened by a wall treatment. You might consider a treatment on the floor before you bring in the whirlpool, unless it's too late.

Ted

 

Soundproofing Company

As most everyone else has (post #192641, reply #9 of 19)

by runnerguy in reply to geoman [original] on Wed, 08/25/2010 - 11:04

As most everyone else has said, there's far better stuff out there then batt insulation. It can be mineral wool insulation or sometimes the stuff is called "sound attenuation blankets" and there can be a BIG difference in mitagating sound.

Story: Many years ago we designed (I'm an architect) a condo project. After the first few building were completed the residents were all complaining of sound problems. We went out there with an acoustical guy and the first thing we found was the builder had just used batt insulation. Our drawings called for something like 3" of sound attenuation blankets calling for an STC (Sound Transmission Coefficient) rating in the 50's. The acoustical guy did his tests and came up with an STC rating in the 20's for the walls.

Big and expensive redo of the interior party walls. We were ok as the architects however. Thank God we got that note correct!!!!!

Doug

There is no lab data that (post #192641, reply #10 of 19)

by TedWhite in reply to runnerguy [original] on Wed, 08/25/2010 - 11:11

There is no lab data that shows there is anything that performs better than humble fiberglass. Here's just some of the data that's been done: http://www.nrc-cnrc.gc.ca/obj/irc/doc/pubs/ir/ir693/ir693.pdf

Anechdotal observation is great, but does not replace hard lab data where variable are controlled / minimized / identified.

Standard R13, kraft faced or unfaced will perform as well as the most expensive exotic insulation in the mid and upper frequencies. For low frequency isolation, cheap fiberglass actually has the edge.

Ted

 

Soundproofing Company

Heck, according to those (post #192641, reply #11 of 19)

by DanH in reply to TedWhite [original] on Wed, 08/25/2010 - 17:29

Heck, according to those charts nothing works.


We are like tenant farmers chopping down the fence around our house for fuel when we should be using Nature's inexhaustible sources of energy -- sun, wind and tide. ... I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that. --Thomas Edison

Well Dan, that's not too far (post #192641, reply #12 of 19)

by TedWhite in reply to geoman [original] on Thu, 08/26/2010 - 06:30

Well Dan, that's not too far from the truth. If you look at the 4 elements of soundproofing, absorption (insulation)  is the least contributive. Id does have some value, but not as much value as the other three. The 4 elements are:

 

-Decoupling

-Absorption

-Mass

-Damping

Ted

 

Soundproofing Company

I was probably working in (post #192641, reply #13 of 19)

by DanH in reply to TedWhite [original] on Thu, 08/26/2010 - 06:44

I was probably working in vibration damping before you were born.


We are like tenant farmers chopping down the fence around our house for fuel when we should be using Nature's inexhaustible sources of energy -- sun, wind and tide. ... I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that. --Thomas Edison

That's great (post #192641, reply #14 of 19)

by TedWhite in reply to DanH [original] on Thu, 08/26/2010 - 06:58

That's great

Ted

 

Soundproofing Company

Commiting a sin? (post #192641, reply #15 of 19)

by Tim in reply to geoman [original] on Thu, 08/26/2010 - 10:23

No. Respiration is not a requirement for interior partitions, insulated or not. Ask this individual, "Breathe what?"

Given that one room is a kitchen and one a bath, I personally wouldn't do anymore than you are planning. Think about, how often is the house chef going to be annoyed by those darn jets while cooking? A media room adjacent to a bedroom? Now, that would be different....

There are many complex and expensive ways to deaden sound transmission through walls and floors. Sound deading insulation is more effective thatn regular FG batts, but not enough to warrant the extra expense, IMO.

Quote: "Sound deading (post #192641, reply #16 of 19)

by TedWhite in reply to Tim [original] on Thu, 08/26/2010 - 10:53

Quote: "Sound deading insulation is more effective thatn regular FG batts"

 

There is no independent data to support that. The link I provided earlier has several hundred partitions tested, and their conclusion was that FG had a slight edge over other insulations in the LF.

 

Some things are worth spending extra on, however exotic insulation for sound isolation isn't one of them..

Ted

 

Soundproofing Company

One place where (post #192641, reply #17 of 19)

by DanH in reply to TedWhite [original] on Fri, 08/27/2010 - 17:02

One place where sound-deadening is important is where the drain from the upstairs toilet runs through the dining room ceiling.


We are like tenant farmers chopping down the fence around our house for fuel when we should be using Nature's inexhaustible sources of energy -- sun, wind and tide. ... I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that. --Thomas Edison

Might I humbly suggest a (post #192641, reply #19 of 19)

by xxPaulCPxx in reply to DanH [original] on Sun, 08/29/2010 - 12:10

Might I humbly suggest a drain pan between the joists leading to a wall.

 

The only thing worse that hearing "flush - whoosh - gurgle gurgle"

is

"flush - whoosh - oh no, oh no - drip drip - patter patter - pour"

Nothing worse at a dinner party that a rainstorm after a toilet flush from an upstairs bathroom.

Don't ask me how I know this... very very well.

YAY!  I love WYSISYG editing!  And Spellcheck!

____________________________________________________

;) what do you recommend to make Thanksgiving day nicer? (post #192641, reply #18 of 19)

by TedWhite in reply to geoman [original] on Fri, 08/27/2010 - 17:31
Too funny

Ted

 

Soundproofing Company