Sorry... another Quietrock vs. Green Glue thread - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
  • 1 Post By Ted White
  • 2 Post By randyox
Thread Tools
post #1 of 4 Old 09-30-2010, 01:13 PM - Thread Starter
Senior Member
chiguy's Avatar
Join Date: Aug 2005
Posts: 281
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Okay, so I've read most of the related threads and see that it appears that two sheets of drywall with Green Glue is somewhat better than using Quietrock. However, I'm curious if those familiar with both products can help me decide if it's better enough to justify the price difference. I'm going to hire out the drywalling job because I just don't have time to do it myself. It's taken me literally years to do all the prep work myself and this job I just want it done in a reasonable time period. Looking at costs, I can get the residential version of Quietrock from Lowe's and have it installed around $50 a sheet. If I go with two sheets of drywall with GG in between, that installed cost would be about $80 a sheet. At that price difference, I'm wondering if the GG combo is superior enough to justify the premium? I'm not trying to achieve perfection, just improve noise transmission out of the theatre room to the rest of the house.
chiguy is offline  
Sponsored Links
post #2 of 4 Old 09-30-2010, 01:52 PM
AVS Forum Special Member
Ted White's Avatar
Join Date: May 1999
Location: Michigan, USA
Posts: 7,779
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Liked: 58
Reasonable question. Let's look at the facts and some data:

#1 The Mass- When we're talking about Transmission Loss (reducing sound travelling from one side of a wall to the next), Mass factors into this heavily (sorry...) The heavier wall will be harder to move and will resist sound better. A sheet of standard 5/8" drywall from Home Depot weighs 70+ pounds per 4x8 sheet. Two sheets gives you 4.5 pounds per square foot. Nice mass.

#2 The Damping- Using a very small amount of a damping compound can reduce the resonance inherent to drywall. This is a good thing. However from a marketing standpoint, a drywall panel can be called "damped" even with an extremely small amount of damping material. There is no standard or guideline for how damped a panel has to be before it can be called "damped."

#3 The performance- $7 Standard drywall + Green Glue performs better than their top performing board, with the exception of their THX board, which is 1 1/4" thick and weighs 200 lbs...

#4 The Waste- There is an average 12% waste factor with drywall work. You can fill the dumpster with $7 a sheet drywall or $50 a sheet pre-damped board.

#5 The Cost- To get remotely similar performance (see the link) you'd have to move up several levels beyond the opening pricepoint Lowes board.

The bottom line is that you will always be able to field install a much heavier, much cheaper and much higher performance board than any pre-damped board available.

Regarding your $80 a sheet figure, Drywall is $7 a sheet = $14. GG for a board = $19.50. Labor runs $6.40 for the second sheet = $39.90. 12% waste of $7 board = $1.68 for the two standard drywalls combined. 12% waste of a $40 board = $4.80
ellisr63 likes this.



The Soundproofing Company
Ted White is offline  
post #3 of 4 Old 09-30-2010, 01:57 PM
Advanced Member
Dixon's Avatar
Join Date: Aug 2001
Posts: 733
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 12
Interesting pricing.

I looked at using the QR 545 board in my room (their top-of-the-line board). I compared that (via bids) with installing three layers of 1/2" drywall with green glue between each layer. The green glue approach was meaningful cheaper (by a few thousand dollars, actually) primarily because of the high cost of the 545 board and what was likely a tougher install with the 545 to get my desired performance (the 545 would have had to be carefully cut with a saw and we would have had to ensure no gaps--with the multilayer drywall approach we had a bit more room for error).

I went with the green glue approach and have been very happy with the results. I obviously can't draw a measured comparison with the 545 (since I haven't used the 545), but I do suspect that the 545 would have been a terrific performer. In the end the cost difference was just too significant and I got comfortable that the green glue option would serve my purposes.

I am not sure which QR you are looking at, but I would worry that anything less than the QR 545 would not perform up to the same level as a multilayered drywall and green glue approach. That is a gut feel--not something I can prove out.
Dixon is offline  
Sponsored Links
post #4 of 4 Old 09-30-2010, 02:40 PM
randyox's Avatar
Join Date: Nov 2005
Posts: 52
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
I just finished drywalling my home theater a little over a month ago. I used two layers of 5/8 inch drywall with green glue in between. Now, after a month of the stuff curing and living with it... all I can say is I am more than pleased! In fact, it has turned out even better than I hoped. My wife and kids have even commented on how wonderful it is. I can be in the home theater room and watch football or a movie and my kids will be upstairs watching tv and neither of us can hear the other... granted, I also treated the HVAC and the floor joists, but the majority of the room treatment was the dual drywall and green glue. Would I do it all over again? In a heartbeat! Just my two cents... hope it helps. Thanks again to Ted for all the help and information!
ellisr63 and Jacknbox5 like this.
randyox is offline  
Sponsored Links
Reply Dedicated Theater Design & Construction

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off