Green Glue Data and Comparison

1) Steven C: Hello, I am so impressed by your data on Green Glue and I'll be looking to buy a lot of it to solve my sound problem. I have neighbours and our wall is separated by a concrete wall, then wooden studs and one layer of drywall. The noise problem is bass, so very low frequency. High frequency doesn't seem to penetrate. I've read a lot about soundboard, rubber mats, resilient channels, clips etc. What would be the most effective way to reduce the low frequency noise? Attaching another layer of drywall to the drywall already in place with Green Glue? Or taking out the drywall already in place, then filling with fibreglass, then attaching two layers of drywall with Green Glue? And would rubber matting help? And would using Quiet Rock sandwiched by Green Glue help?

2) bill: due to ceiling height restrictions, I will only be able to double up 5/8 drywall in part of my basement ceiling. would just doing the main parts of the basement do much good?

3) Chris: trying to eliminate noise from toilet fill-up in adjoining room. Can only address bathroom side wall which is 2x4 16' o.c. Is another layer of 5/8 sheetrock with green glue sufficient in your estimation. Wall is insulated. Thanks

4) Carl: Hello, I am planning to use whisper clips and resilient channel for my project (isolation room for acoustic drums and other loud instruments) and am trying to decide whether it would be worth the extra $600 it would cost to also use green glue. I can't find any test data for green glue + whisper clips. Do you have any data or insight on how much additional sound reduction I might achieve by using the green glue as well? Thanks! Carl

5) Richard: Hi I am looking to reduce airborne noise from flat below mine. I cannot alter their ceiling (single sheet). There is now 100mm acoustic wool between joists. My floor is a pretty darned flat T&G. Can I apply Green glue direct to the T&G and overlay with dense chipboard? Would the Green Glue work effectively in this application and add much attenuation over that provided by the additional mass of the chipboard please? Many Thanks Richard

6) Michael: Hello I am interested in using greenglue and adding drywall to fix a soung problem without taking down the wall. How much better is it to use a third dry wall w/ green glue application? (5/8 drywall - GG - 5/8 dry wall - GG - 5/8 dry wall). Is this worth the trouble? Is there any other solution you may suggest that does not involve tearing down the existing wall. Thank you!

7) Rosie: I would like to install LVP in a 2nd floor condo and am looking for the best solution to block airborne and impact sound. Is it important to sandwich green glue between the same substrate or could I apply green glue to the existing plywood subfloor and cover with 1/2” cement board. I would put acoustic rubber over the cement board as an underlayment before installing the LVP.

8) Glenn T: I need to put in a subfloor assembly existing of 3/4' T&G plywood, followed by 2 layers of 1/2' Durock. Would green glue be beneficial between the 2 layers of Durock -- estimate of how much improvement?

9) James: I read from past posts that yes, I can sandwich green glue on the plywood subfloor and another layer as long as they are 1/2' thick. Is there a particular product for the top layer that would work best for soundproofing? more plywood vs osb vs cementboard etc...? Thanks.

10) Mike: Can Green Glue be used in car interiors? And in place of MLV? tx.

11) Aaron: I'm converting a bus into an RV and looking for the best solution to isolate exterior noise (mainly engine/mechanical/tire/road). It's 40' rear engine with a Cummins ISC 8.3 diesel, the engine situated in a rear 'bench' or 'deck' type setup that will be getting special attention (all of whats noted below and more -- possibly a lead sheet and engine-compartment CLD tiles). The bus has frame rails that run the length of it also, dispersing energy to increase the challenge. The interior is stripped down to the sheet metal on the floor, and I'm trying to devise the best soundproofing/insulation plan, and it seems adding an extra layer of OSB to add Green Glue to the mix may be wise. The current (in-development) plan is 30% panel coverage of vibration dampener sheets, 3/4' XPS foam for a thermal break, steel studs with either Rockwool, Thermafiber, or cellulose as the acoustic insulation layer in the stud cavity, then additional acoustic treatment layers. Those additional layers are coming into question after coming across this product. I was planning to use MLV as the very next layer, then Advantech. To incorporate Green Glue, I'd be adding another layer of 1/2' OSB between the MLV and Advantech, and putting Green Glue between them. Any recommendations here on placement, or suggestions? I'm also planning to have a radiant heating layer, though haven't decided yet exactly where to place that (cost-factor, too). And I'm still working on a similar plan for the walls, but not as thick as it'll remove too much living space. Thanks!

12) Nk: We are looking to soundproof one side of a home close to a highway with lots of truck traffic. So it’s vibrations as well as the actual noise. What do you recommend?

13) Luke: Are you aware of any independent lab test results of Green Glue vs the 5/8' Quietrock or other similar products? I believe these test results are published by Green Glue, correct? Also, is there a comparison of Green Glue vs 5/8' Quietrock + 5/8' drywall? That seems like a much more fair comparison than Green Glue (2 sheets of 5/8' drywall) vs a single sheet of 5/8' Quietrock. The Green Glue setup benefits from an additional mass layer of drywall but is presented as if it is apples to apples.

14) nicholas barra: I am on the first floor of a condo. The ceiling is comprized of 2 layers of 5/8 drywall and 3 1/2 inch of fiber insulation. The floor of the second floor unit is plywood , finished with hard wood and tile no carpet. The sonud of footsteps and chairs viberating is overwelming. My thought is to add a layer of green glue to CertainTeed's Silent FX soundproofing drywall. This would create 2 layers of green glue and only drop the ceiling 5/8'. Will this work. What type of STC increase could I expect? Thank you Nick

15) Marty Wolcott: What thickness MLV was used in the Green Glue / MLV test: 1/16', 1/8' or 1/4'? Do you have numbers for all three?

16) LP: What do you think of making a 5/8 drywall // mass loaded vinyl // greenglue // 5/8 drywall sandwich? Is there a downside to have the greenglue sticking on the mass loaded vinyl?

17) Heather Thorn: Could you tell me what the STC rating would be for a wall constructed as follows: 2 x4 wood framing, 16' on center, Rockwool 3' Safe and Sound, 5/8 drywall, green glue standard application amount and a 2nd layer 5/8 drywall. Am I reading previous questions right, that the first layer of 5/8 will give you about 8 STC points and the second 5/8 Layer and additional 4 points? What is the STC point reduction for Green Glue? Thank you Heather

18) Ryan: Hello, I am converting my crawl to a basement for a pool table and golf simulator- so lots of high pitch noise. Is MVL, 5/8” drywall, GG, 5/8” drywall plus clips better or is Is three layers of drywall and 2 layers of GG plus clips better? Or another way? Thanks

19) TMG: I am building a sound deadening box (18’ x 10” x 12”) to muffle the noise produced by an electrically powered high pressure, three piston water pump. Unmuffled, a (free, iPhone app) acoustic meter reads 70dB, peak frequency of 80 Hz, at distance of 5 feet from operating pump. Usual seating position is 15 feet from pump’s location, so it’s appreciably quieter at that distance, though still rather annoying. The pump is part of my veranda’s mist cooling system; it’s placed on the concrete floor. It requires fan-driven ventilation at the back (inlet) and front (exhaust) of the pump. Openings for this ventilation are 4”x4” square at inlet and 3.5” diameter circular hole at outlet. The box includes openings which replicate these louvered openings in the pump’s casing. Your suggestions/feedback on following overall plan: Six-sided box with following layers, from inside out, on top and 4 sides: 2lb MLV (attached with screws), 3/4” MDF, Green Glue, 3/4” MDF, 2” thick pyramidal sound foam. Bottom of box is single layer of MDF with 2lb MLV screwed to upper face; it does does NOT have the sound foam, Green Glue, or second MDF layer, but does include four 4” x 4”, 1” thick vibration isolation pads on the underside to decouple from the concrete floor. The box is held down onto the bottom piece using multiple loops of lightly stretched shock cord to ensure minimal sound leakage at side/bottom interface. The MLV on the bottom extends ~ 3/4” beyond the outer edge of the box on all sides. All inside joints are caulked and taped; box assembled very tightly with glued and nailed butt joints (accurately cut; I’m a woodworker). Over each ventilation opening, stand-off spacers of ~ 1.25”, then a 5”x5” piece of 3/4”MDF with 2lb MLV screwed to face closer to box. These are intended to allow sufficient airflow while forcing sound to “make a 90 degree turn” before reaching my delicate ears. Several much smaller additional openings for water tubing and electrical cable; no baffles on these. Over the box described above is placed a second, 5-sided, much larger box (24” square) of 1/2” MDF with 2” pyramidal foam glued to all inside surfaces. Joints caulked, glued, nailed as with smaller box. Crushable weather stripping along bottom edge to minimize leakage at box/concrete floor interface. Larger box includes ventilation openings as on smaller box, and aligned with those in smaller box. No sound baffles on larger box’s ventilation openings. This box also conceals the filter and excess water tubing; it is painted to match the veranda walls’ color. (This beautification serves to reduce spouse-generated noise). I anticipate receipt of my (single tube) of Green Glue this afternoon; very soon I’ll be adding that and outside 3/4” MDF layer to inner box. Suggestions? Anything missing, or “unsound” in this plan? Any guesses as to degree of noise reduction I may realize with this approach? Any help much appreciated.

20) Judith Parmelee: I have an existing floor where we are putting in a basement unit below. The height is tight. We will have 5/8' gyp bd on channels for fire. Above the client would like tile floors but I need to keep thickness at a minimum. It sounds like I can add green glue and 1/2' cement board over the sheathing in application. Is that correct? However, I need a tested assembly number with an STC & IIC of 50 min. I see your lab test shows STC makes that but IIC doesn't. What can I add to improve IIC a few points?

21) Sharon Young: I have a small boutique hotel in an historic building and after completely finished and up and running we are getting a lot of complaints of tv and voice sounds from adjoining room and in the hallways, etc. Trying to do the least invasive approaching that will address this issue. Will additional layer of drywall and green glue help enough to curb the complaints?

22) Lenska Bracknell: My bedrooms are downstairs and upstairs is the living space with footsteps on the laminate flooring which is newer. What is the best solution to soundproof the downstairs ceiling. Currently I have insulation and 5/8 drywall. I like to avoid tearing down the ceiling but rather add green glue plus drywall or can I use the channels over existing drywall? Or am I better off using green glue plus another layer of drywall. Your expert advice is much appreciated.

23) Joe: We are about to close on a home which has a 15ft high wall in the family room. Redoing that side would be cost prohibitive, however that height is split between two levels on the other side. On the upper level I want to make a music room. What would be best solution to minimize noise and vibration transfer when only treating the one side of the wall? I’m