Author Topic: Green Glue  (Read 15384 times)

SueBee

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Green Glue
« on: June 28, 2006, 05:06:48 PM »
Hello,

Had anyone tried the Green Glue product?  The way I understand that it works is you glue drywall to your existing drywall and it's supposed to be better than MVL.   :o

Is MVL still recommended with Green Glue?  Should the existing wall be taken down to add insulation first?

Thanks,
SueBee :)

johnbergstromslc

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Re: Green Glue
« Reply #1 on: June 28, 2006, 08:33:05 PM »
I've tried it, and I likes it!

You've got it right; you basically glue another sheet of drywall to the first layer (with a limited number of fasteners) and you get some good mechanical damping that helps deaden sound, esp. lower frequency sound.

There are some things you can do with an MLV/Green Glue combination, but to get it right is a bit too complicated for the casual remodeler.  Safer to stick with just G.G.

It is preferable to tear down the existing drywall and insulate the wall, but you have to judge if the additional work and expense (drywall is up to $8 a sheet, I think) is worth it.    


SueBee

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Re: Green Glue
« Reply #2 on: June 28, 2006, 10:44:17 PM »
John,

Thanks for the reply!  What would you suggest to insulate the wall with?

SueBee   :)

johnbergstromslc

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Re: Green Glue
« Reply #3 on: June 29, 2006, 02:18:36 PM »
Good, ole fiberglass works.

It's the cheapest and you can do it yourself.  Since it's just for sound, it doesn't have to be a perfect installation, just cover the whole stud cavity and get it at least 75% full.

hickory_stick

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Re: Green Glue
« Reply #4 on: July 03, 2006, 04:32:33 AM »
Sorry to disagree, but 1970's technology fiberglass doesn't work well in the field, (maybe in the lab).  A superior material for filling the walls is Absorbent recycled cotton fiber.

Hick

johnbergstromslc

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Re: Green Glue
« Reply #5 on: July 03, 2006, 02:59:26 PM »
Sell cotton insulation, do you?  Sure sounds like it....

Fiberglass is not the 'ultimate' acoustical material, but it works pretty well.  Look at the THOUSANDS of acoustical tests on partition transmission loss and tell me what they are filling their walls with, when absorbtive insulation was a variable in the test.  Find me two tests, one with fiberglass and one with cotton, with all other variables the same, and show me the glaring difference.  I bet (some serious money) you can't.  

Oh, but you said, "in the field".  Well you may be right under one condition - fiberglass put in by a blind, retarded, limbless installer will probably not work too well.  But the same applies for cotton.  But any competent insulation installer (or homeowner with half-a-brain, staple gun and an instruction sheet, if they are a novice) can attain the same level of coverage and performance as in a lab-constructed wall.  And, if there are large imperfections, it will only amount to one or two dB reduction, at most, which, at 2 dB, will only be perceptible to 4% of the population, mostly teenagers whose hearing has 'peaked'.  Us 'old guys', people in our 30's+, the ones who actually have money to do serious soundproofing (and frequently are trying to isolate the noisy teenagers, no less) won't notice a 2 dB difference.  It's not worth even worrying about.

Again, I challenge you to show me the myriad "in the field" tests of cotton vs. fiberglass and how they compare.  What's that, you can't?  That's because THERE AREN'T ANY!!!!!  The only way to reliably test and get reproducible results is IN THE LAB.  It's too expensive to test in the field and there are many uncontrolled variables - deviation from established plans, flanking noise, inconsistent screw spacing, hungover drywall installers, etc. etc.  Unless you are constructing a high-end luxury building, where peace and quiet is expected (and you have an extra 10+ grand in the budget to do acoustical tests) you don't test STC/IIC/OITC in the field.    

Cotton costs 3 TIMES AS MUCH, to fill a given wall cavity.  Does it work 3 times better than fiberglass (achieving 15-18 dB absorbtion of resonant sound)?  No fu**ing way on earth.  Does it even achieve 1 dB better?  Extremely unlikely.

And even though cotton is treated to resist fire, it is still infinitely more combustible than fiberglass, which, except for it's paper facing, simply will not burn.

In addition, you can get a roll of fiberglass down at your local Home Depot or Lowes, with no waiting, no shipping costs, none of the hassle or uncertainty that is involved with ordering online.  You can be sure you're buying a quality product, rather than risk receiving a 'bum roll', something previously used, returned, then dumped off on you, arriving all torn up and dirty.  I've seen it happen!  And made some good money on the homeowners disgust, too!  

If you want to use cotton to mindlessly feel good about yourself and think, "I'm saving the world by going organic!!", then go ahead.  But you're wasting your money.  If you want to save the world, much better to get rid of your SUV.


John

P.S.:  I don't sell fiberglass, nor do I have any affliation with any retailer, distributor, or manufacturer of fiberglass insulation.  I'm just a guy who knows better than to get ripped off.

supersoundproofing

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Re: Green Glue
« Reply #6 on: July 10, 2006, 04:31:28 AM »
Quote
Sell cotton insulation, do you?  Sure sounds like it....

Fiberglass is not the 'ultimate' acoustical material, but it works pretty well.  Look at the THOUSANDS of acoustical tests on partition transmission loss and tell me what they are filling their walls with, when absorbtive insulation was a variable in the test.  Find me two tests, one with fiberglass and one with cotton, with all other variables the same, and show me the glaring difference.  I bet (some serious money) you can't.  

Oh, but you said, "in the field".  Well you may be right under one condition - fiberglass put in by a blind, retarded, limbless installer will probably not work too well.  But the same applies for cotton.  But any competent insulation installer (or homeowner with half-a-brain, staple gun and an instruction sheet, if they are a novice) can attain the same level of coverage and performance as in a lab-constructed wall.  And, if there are large imperfections, it will only amount to one or two dB reduction, at most, which, at 2 dB, will only be perceptible to 4% of the population, mostly teenagers whose hearing has 'peaked'.  Us 'old guys', people in our 30's+, the ones who actually have money to do serious soundproofing (and frequently are trying to isolate the noisy teenagers, no less) won't notice a 2 dB difference.  It's not worth even worrying about.

Again, I challenge you to show me the myriad "in the field" tests of cotton vs. fiberglass and how they compare.  What's that, you can't?  That's because THERE AREN'T ANY!!!!!  The only way to reliably test and get reproducible results is IN THE LAB.  It's too expensive to test in the field and there are many uncontrolled variables - deviation from established plans, flanking noise, inconsistent screw spacing, hungover drywall installers, etc. etc.  Unless you are constructing a high-end luxury building, where peace and quiet is expected (and you have an extra 10+ grand in the budget to do acoustical tests) you don't test STC/IIC/OITC in the field.    







Cotton costs 3 TIMES AS MUCH, to fill a given wall cavity.  Does it work 3 times better than fiberglass (achieving 15-18 dB absorbtion of resonant sound)?  No fu**ing way on earth.  Does it even achieve 1 dB better?  Extremely unlikely.





And even though cotton is treated to resist fire, it is still infinitely more combustible than fiberglass, which, except for it's paper facing, simply will not burn.

In addition, you can get a roll of fiberglass down at your local Home Depot or Lowes, with no waiting, no shipping costs, none of the hassle or uncertainty that is involved with ordering online.  You can be sure you're buying a quality product, rather than risk receiving a 'bum roll', something previously used, returned, then dumped off on you, arriving all torn up and dirty.  I've seen it happen!  And made some good money on the homeowners disgust, too!  

If you want to use cotton to mindlessly feel good about yourself and think, "I'm saving the world by going organic!!", then go ahead.  But you're wasting your money.  If you want to save the world, much better to get rid of your SUV.


John

P.S.:  I don't sell fiberglass, nor do I have any affliation with any retailer, distributor, or manufacturer of fiberglass insulation.  I'm just a guy who knows better than to get ripped off.




<B> John, you mean well but you are wrong to denigate someones opinion because they might "sell" something.  
Literally hundreds of people have called us (The Super Soundproofing Co), to complain they were sold fiberglass and got ripped off because it doesn't work well, or at all.  
(Not to say that some of our imulators wouldn't!  See

http://www.soundproofing.org/sales/how_to_select.htm )

You need to go with us into the field where these products are used and verify their effectiveness.  Do you REALLY think we would or could sell materials that don't work as well an alternative to cheap fiberglass you can buy at the Home Depot?  Get real, you can't base a reputable company on that premise.







You certainly are entitled to your opinion, but it is still (Like others), just an opinion, not fact.  

Owens-Corning will admit, if you press them, (as we and others have), that the effectiveness of fibrerglass insulation is "subjective" in the field.  Try it, call them and press them- they will tell you that "Marketing" sometimes "has overblown" the results.

After nine years in this industry, we would never sell something "just to make a buck".  We have to know that it works and works well or would never sell it.







The notion that someones opinion is suspect because they might be "selling" a certain product is juvenile.  Just because one is not selling something does not give an opinion more validation- actually shows less credibility because if one doesn't use it and have experience with it,  one therefore can't really critique it.







The Forum is for an exchange of ideas on the subject of sound control and I for one truly appreciate your many contributions!


BJ Nash
Super Soundproofing Co

And We DO shamelessly sell all kinds of appropriate soundproofing materials!
[/B]
Super Soundproofing Co
www.soundproofing.org

johnbergstromslc

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Re: Green Glue
« Reply #7 on: July 10, 2006, 10:44:43 PM »
BJ:

Although I am extremely skeptical that cotton offers any advantage over fiberglass, I am not completely closed to the idea.  The problem is proof - where is it?  If you (or anybody) can find a controlled test (same lab/field conditions, same level of quality control in installation, etc.) comparing fiberglass and cotton and show me that cotton is superior enough to justify the added cost, then I will gladly eat my words.  (And switch to cotton, too!)

You said that people call your company complaining about fiberglass, that it doesn't work.  How do you know it was installed properly?  I also think in many of those cases, the homeowner was expecting 'miracle' results from just throwing some insulation in the walls.  He/she didn't bother with resilient mounting, decoupling, additional mass, or sealing.  In that case, fiberglass would help a little bit, but not enough to meet the unrealistic expectations of the homeowner.  Many of the questions I have seen on this forum tell me this 'short cut' attitude is prevalent.  

Maybe you should spend a few thousand bucks and do some acoustic field testing of cotton vs. fiberglass.  It would be a great marketing tool.

Otherwise, your assertion is also just an opinion.  

I have no problems with people making money (in fact I've probably made you some money by recommending some of your products), I just think that your employees should identify themselves as such when they post, so people know they're being given a sales pitch.  


noisetwentyone

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Re: Green Glue
« Reply #8 on: July 13, 2006, 09:27:45 PM »
For what it's worth, recycled cotton fiber materials do not require a carcinogen warning on the label, it does not contain formaldehyde, it doesn't itch and does not require protective clothing during installation. It is also a "green" product, environmentally safe and it doesn't cause air quality issues.

Good point though John on comparative acoustic tests. Both Johns-Manville and Owens Corning seem not to publish acoustic testing anymore. I seem to remember some years ago that the fiberglass industry claimed an STC improvement of 5 for the first inch and 1 or two for every inch thereafter.

joel

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Re: Green Glue
« Reply #9 on: August 04, 2006, 07:04:38 PM »
Hi SueBee,

The most simple way Green Glue is used with MLV is as follows:
Apply MLV directly to existing wall (get the MLV with PSA - pressure sensitive adhesiv back - for a peel & stick application w/no odor).  Next is a layer drywall.  Then apply Green Glue and add finish layer of drywall.

Joel    

jamesboyd

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Re: Green Glue
« Reply #10 on: August 29, 2006, 02:20:08 AM »
THis guy John.. I love him! Go man go.

Show me da money... er, data!

joel

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Re: Green Glue
« Reply #11 on: August 30, 2006, 12:28:56 AM »
Hello SueBee,



We have used Green Glue by itself sandwiched between both existing drywall and new construction drywall.  We've also used it with OSB and plywood and soundboard sandwich for subfloors and floor applications.  It is NOT better than MLV - it is an entirely different form of sondproofing and sound dampening.  In fact we have gotten spactacular results using Green Glue WITH MLV and drywall, OSB, etc.



If you want to add sound absorbing and blocking insulation inside the contained space between studs in a wall assembly, then use bonded cotton insulation.  It will add 1.15 NRC and 20+ STC INSIDE the wall cavity.  See  http://www.soundproofing.org/infopages/natural_fiber.htm  







If you want to work your soundproofing directly to the existing wall you can add a layer of MLV to existing (it is available with pressure sensitive adhesive back for a "Peel & stick" application - no staples or glue smell) and then use 2 tubes of Green Glue per 4x8 sheet of drywall.  Apply the Green Glue directly to dry wall or MLV and then screw the drywall on as usual.  The Green Glue takes about 2 to 3 weeks to fully cure (it will wick into the drywall as it cures inside the sandwich).  You will get the immediate sound barrier affect of the MLV and, when the Green Glue cures, the resonant frequency of the wall assembly will drop - dramatically improving the bass frequency blocking.  This gives you the best of all soundproofing worlds - instant gratification and improving results over time!



For MLV info see http://www.soundproofing.org/infopages/flooring.htm and for Green Glue see http://www.greenglue.org/ggsoundproofing.html



Joel