Are you like me and trying to choose between QuietRock vs double drywall to soundproof walls and ceiling in your media, games or bedroom? Determining which will give the best results for the price can be difficult.
Which Is Better for Sound Reduction? QuietRock or Double Drywall? QuietRock can improve the soundproofing by 15 to 20 points on the STC scale, while it will take up to four sheets of drywall to have the same effect. If you’re doing both sides of a partition wall, that’s 2 sheets of QuietRock for 8 of the gypsum.
In this article, I’ll take a look at QuietRock and compare its installation and soundproofing with regular drywall. I’ll also look at the similarities and differences of soundproof with QuietRock vs. double drywall.
What is QuietRock Sheetrock?
QuietRock is a sound damping product that has a viscoelastic material sandwiched between two gypsum layers. The gypsum has the mass to block soundwaves, and the viscoelastic material damps the wave vibrations. Combined the sheet will reduce the transmission of sound in or out of a room by between 15 and 20 STC points when compared to standard drywall sheets.
The sheets are available in thicknesses of 1/2″, 5/8”, and 1-3/8”, with dimensions of 4’x8’, 9’, or 10-feet. The lengths are tapered for taping and mudding, plus it can be scored and snapped the same as regular sheets. The 5/8” 4×8 sheet weighs 83.2-pounds (2.6 lbs/ft²). Prices of building materials like drywall and QuietRock fluctuate, so check with suppliers for current prices.
Types of QuietRock Panels
5/8” thick 4×8’, 9, or 10’’ sheets that score and snap easily, and can be used the same as standard drywall, but with better soundproofing performance. The panels attach directly to the studs or joists, so takes up less space than other standard drywall attenuation techniques. A 4×8 sheet weighs 83.2-pounds and has an STC value between 48 and 60 depending on wall construction.
EZ-SNAP Mold Resistant
Similar to EZ-SNAP but with mold-resistant paper and soundproofing core material. A 4×8 sheet weighs 83.2-pounds and is ideal for damp locations or bathrooms. Depending on wall assembly, it has an STC rating between 48 and 60.
QuietRock 510 ($55-$60)
A less expensive option, the 1/2″ thick 4×8’, 9, 10’ and 12’ gypsum panels also have a sound damping core. They can be installed directly over existing drywall to improve STC rates to between 47 and 52.
QuietRock 530 ($105-$110)
A denser 5/8” panel available in 4×8’, 9’, 10’ and 12’ sizes, and the 4×8 weighs 105.6-pounds (3.3 lbs/ft²). It is shear rated for almost 500-pounds and has an STC 52 and 74 depending on the construction methods used.
QuietRock 530 RF
The 530 RF is the same as the 530, but with added shielding against radio frequency penetration to provide high security for information-sensitive locations. Installation requires different preparation to ensure the radio frequencies are blocked, and a skill saw to cut or trim. It is impact resistant and can be used on walls, ceilings, and floors for full protection and STC rankings between 52 and 74.
An 11 layered high-performance drywall panel that is recommended for home or commercial studios, sound rooms, or theaters. The 1-3/8” thick 4×8’ sheets are a hefty 200-pounds (6.25 lbs/ft²). They have tapered edges and are STC rated between 60 and 80 depending on wall construction. 545 works well even on low-frequency noise too.
The benefits of using QuietRock over other drywall products are many. Layer to layer it provides better sound attenuation, which reduces the need for additional layers, resilient or hat channels, and viscoelastic material. Time and budget constraints are additional savings as a wall can be finished in one pass, instead of multiple passes for different layers of material.
A single layer of QuietRock also means you don’t give up floor-space to additional layers too. The panels finish the same as regular drywall, have an equivalent fire and smoke rating, but reduce noise transmission better.
The sound transmission class (STC) is third party verified, so it isn’t skewed like some big companies do. The STC ratings are based on wall construction, not individual panels. That means to achieve comparable values; wall construction needs to be similar. The Product Datasheet for each QuietRock product provides images of the wall assemblies and the STC. It is also recommended that soundproof caulking be used to seal the 1/4″ gap left where the wall meets the ceiling, floor, and other walls or openings.
QuietRock is fire rated similar to regular drywall compositions; one-hour rating for 5/8” sheets, the 1/2″ thick 510 panels have not been tested for a fire rating. I also couldn’t find a rating for the 1-3/8” thick QuietRock 545. However, I presume it would be equal or better than the 5/8” rating. When gypsum is heated to high combustible temperatures, it will produce steam as trapped moisture evaporates.
QuietRock on Ceilings
Quiet rock can be used on ceilings to block airborne sound. Like most other drywall material, it doesn’t handle impact noise isolation. QuietRock can be attached directly over existing drywall that is attached to the joists, not to resilient channels. It also should be screwed through the existing gypsum layer and into the joists. QuietRock does not recommend the 510 product for use on ceilings due to the possibility it may sag.
Where to Buy QuietRock
The QuietRock website has a dealer locator for a location near you. The dealers may have some products in stock but not the whole product line. You will most likely need to order in depending on product, dimensions, and the number required.
The installation of QuietRock is similar to that of regular drywall in standard applications. It should be fastened directly to the studs or to existing drywall with appropriate screws. Leave a 1/4″ between the panels and the ceiling, floor, and adjacent wall to be filled with acoustic calking.
QuietRock has a viscoelastic material inside it which damps vibration. For partition walls with 3.5-inches of insulation and wood studs every 24-inches, an STC rate of 51 can be achieved using EZ-SNAP, and an STC of 52 with QuietRock 530. Using the same insulation but with 3-5/8” steel studs at 24” centers instead, and the STC climbs to 55 and 56 respectively.
QuietRock 545 on a single stud wall has an STC rating of 56. Decoupling the wall with a double-thick stud wall and 545 takes the value to 75. Doubling up the 545 on that type of wall construction produces a quiet value of 80. However, you’re also losing 2-3/4” off the perimeter of the room.
- One 5/8” layer provides sound stopping results
- Saves on labor and material costs
- Heavier, so more sound stopping mass
- Better STC values than regular drywall on similar wall construction.
- Difficult to use for ceilings
- Not good for decoupling and blocking mechanical or impact noise
Types of Drywall
Drywall is sheets of gypsum wrapped in paper and commonly has tapered edges on the long sides for tape and mudding. It is known by different names and brands, such as wallboard, gypsum, gypsum board, plasterboard, and Sheetrock – which is a brand name. Different thicknesses are available for specific uses and products. The thicker materials are denser and offer more mass, which helps decrease sound transfer.
Regular or White Board drywall panels are available in 1/4” to 1” thicknesses, and 4×8’, 9’, 10’ and 12’ dimensions. Longer sheets can be special ordered. The paper on the room side is whitish, and the back, or wall side, is brownish.
Green Board is a moisture-resistant gypsum sheet. The green covering is more impervious to moisture. It isn’t waterproof but is frequently used as a backer for tiles in bathrooms, kitchens, and laundry rooms.
Blue Board is more water and mold resistant than Green Board, and is often used for plaster finishes. It has special absorption properties for use with plaster finishes; the paper isn’t made for taping, mud, or paint.
Paperless Gypsum is covered with fiberglass instead of paper and resists moisture, mold, and mildew much better. The fiberglass covering isn’t smooth, so a slick coat of joint compound is required for a smooth paint finish. The boards are also more durable than the paper coated gypsum.
Purple covered gypsum panels are similar to regular sheeting but have better moisture and mold resistance. It is ideal for basements or bathrooms where water contact is likely.
Type X is made with non-combustible material and is referred to as fire-resistant. To be fire-rated a 1/2″ thickness must achieve 3/4-hours of fire resistance, and a 5/8” thickness an hour. Required by building codes for specific locations, it commonly is used in apartments, schools, meeting rooms, and garages.
Soundproof drywall sheets have a layer of sound stopping material sandwiched between two layers of gypsum. It is denser than comparable thicknesses and blocks more sound movement. Frequently used in media rooms, or rooms requiring less noise intrusion or disruption.
For comparison with the QuietRock, the wall assemblies are the same. A wood stud wall with regular 5/8” drywall and 3-1/2” of insulation has an STC of 46, with steel studs that will improve that to 49. Doubling the drywall on steel studs brings the STC to 58, plus it doubles the fire rating to 2 hours. Doubling the drywall on wooden studs with insulation has an acoustic performance of 52 and two hours of fire rating.
Drywall with Green Glue Assemblies
Using Green Glue to damp sound requires two layers of drywall. The first layer of gypsum is attached to the studs. A coating of Green Glue is applied to the second sheet of drywall before it is attached to the first. Offset the seams of the second layer from those of the first, and to screw to the drywall, not the studs. The “glue” is compressed between the two layers and forms a spongy layer that absorbs sound vibrations.
Double Drywall benefits
The benefit of a double thickness of drywall with Green Glue sandwiched between is less noise penetration. The drywall adds mass, which prevents sound wave penetration, especially lower frequency, and the Glue absorbs sound vibration-damping sound vibration movement.
QuietRock vs Double Drywall Comparison
When soundproofing a room or space, remember that the aim is to decrease the transmission of sound into or out of a room. It won’t be soundproof; it will hopefully be quieter. Whether renovating or building, the cost is always a factor, as is time – which is also money. Adding QuietRock over an existing layer of drywall will add to the mass and reduce sound transmission. It will improve the STC value by about 5 points. Drywall addresses the mass requirement, and works best for airborne sound, not impact or flanking noise.
The cost of 5/8” QuietRock EZ-SNAP is $60 to &65 for a 4×8 sheet, and 530 is $105 to $110.
The cost of 5/8” regular (non-light) drywall in my area is $12.57, so 2 sheets will cost $25.14.
A 5-gallon pail of Green Glue is about $260 and will do 365 square feet, or just over eleven 4×8 sheets, so about $23.60 a double panel.
The math works as follows: $25.14+$23.60=$48.74 for a 4×8 section of wall using double drywall vs. $60 to $110 for a layer of QuietRock. The sound transmission class ratings are compared in the table.
For a 10ft by 10ft room, the costs for doubled 5/8” regular drywall and Green Glue would be $487.40. The same room in one layer of either EZ-SNAP or QuietRock 530 is between $600.00 and $1,100.00.
|2×4 Wood Stud Partition Wall (24” spacing) With 3-1/2” Fiberglass Installed|
|1/2-inch layer drywall on each side (1.6 psf)||42|
|1/2-inch QuietRock 510 panel installed vertically on each side (2.1 psf)||52|
|1/2-inch double layer (1” thickness) drywall on each side (3.2 psf)||46|
|5/8-inch layer drywall on each side (2.3 psf)||48|
|5/8-inch layer drywall on each side with resilient channel||51|
|5/8-inch EZ-SNAP QuietRock panel installed on each side (2.6 psf)||51|
|5/8-inch QuietRock 530 panel installed vertically on each side (4.1 psf)||52|
|5/8-inch double layer (1-1/4” thickness) drywall on each side (4.6 psf)||54|
|5/8-inch double layer (1-1/4” thickness) drywall on each side with Green Glue||59|
How to Improve Acoustic Performance
Making a room quieter means addressing the four elements of soundproofing – absorption, damping, decoupling, and adding mass. Drywall with Green Glue and QuietRock add mass and damping and address airborne sound. They don’t address mechanical (impact) or flanking noise. Check out How to Soundproof a Ceiling, and How to Soundproof Walls for further information.
Outlets, switch boxes, light fixtures, and vents are possible ways for sound to by-pass your drywall soundproofing efforts. Frequency vibrations can bounce from room to room unless they are damped too. Putty pads are a viscoelastic material that can be used to wrap electrical boxes and vents to quiet noise transfer.
Acoustic caulking is another way to damp vibration movement. There should be a gap between the drywall and the floor, ceiling, and adjacent walls. Filling the gaps with the caulking helps prevent sound movement.
Resilient clips and channels are an effective way to decrease vibrational sound waves by decoupling the wall layers. Use of resilient clips and channels can improve the STC by between 12 and 15 points.
Reducing the sound disruption in your home or business is a matter of controlling the four elements of sound – adding mass, damping, absorption, and decoupling. Adding fiberglass or rock wool between the studs adds absorption, and double-drywall with Green Glue or QuietRock add mass and damping.
QuietRock will take up 5/8” of floor space while double-drywall uses 1-1/4”, so if space is a factor and cost isn’t, then I’d recommend the QuietRock. However, the STC improvement between a single layer of regular 5/8” gypsum and the EZ-Snap is only 3 points, which in the world of noise, isn’t much. If you are serious about stopping the sound, doubling the drywall and adding a viscoelastic material like Green Glue, bump it 8 to 11 STC marks. Now that is sound stopping!
Hope you found this article of value. If you know someone who might benefit from it, pass it on. Your comments and suggestions are always appreciated.
81 thoughts on “QuietRock vs Double Drywall: Which Is Better for Soundproofing?”
Thank you for the information
Ok my current party wall is double 5/8” drywall both sides 3-5/8” metal studs. I hear talking but
(unrecognizable) mostly their bass music or when they are playing video games. With your article it sounds like green glue and two layers of 5/8” drywall(on top of the existing wall) will help better than one layer of quite rock. I’m just asking for confirmation about my decision with your articles help
hello.i have an older apt that i want to sound proof.over the past 3 days i put in around 4 hours on the internet in an attempt to educate my self.your article has completely answered all my questions and now i can go forward with my sound proofing.thank you. richard in vernon ct
Very informative and well written. Thank you. I now understand exactly what I need to do for my project.
Question: Can I put the quiet rock up without using sound proofing glue between the quiet rock and existing sheetrock?
Thanks Eugene! Your insight is exactly what I needed! Sam
Very informative. Thank you!
Question if you have a moment…
My house is old, 1784 old and the kitchen has great exposed beams. I plan on drywalling the ceiling but only between the beams to keep them exposed. Currently you can hear everything from the room above so I planned on using Quietrock to cut the noise at least a bit. Is it pointless in this type of application or will it give me at least a bit of help with the sound?
I have a very specific question. I do music recordings, and the thudding of footsteps (and voices) is awful in my studio. I obviously need to soundproof my ceiling.
Money is NO expense…but space is. I have 1 3/4 inch of space before the job gets more complicated and interfering with the AC vents.
What’s the absolute best soundproofing job you think I can do with only 1 3/4 of space?
I assume I would leave the existing ceiling be and just work under it (easier and cheaper). If there is no way I can achieve massive sound reduction with the limited space I have then I might just have to rip open the ceiling?
This is exactly the write up and comparison I’ve been looking for! In the last paragraph are you comparing QuietRock ezsnap or QuietRock 530 to double layer of 5/8 with green glue?
Also I gather that QuietRock 530 has a better stc rating than ezsnap?
I really appreciate your research and valuable information! I am still not sure the best solution to dampening/eliminating the droning, vibrating sound coming through my walls on one side of my condo. The building has the air condition units mounted to the roof which sends the vibrations through my walls whenever other units run their air or heat. Maybe a combination of methods?
Adding 5/8″ drywall with Green Glue sandwiched between will certainly help because of the mass. You may also want to give some consideration to decoupling because of the vibration. Resilient channel or isolation clips and hat channel applied to the existing drywall, then covered with 5/8″ drywall. this will give you the mass for dampening and the decoupling to cut down vibration. (The resilient channel will add about 1″ to the wall. Clips and hat channel will add over 2″.) Whichever method you choose, you will have to extend plug, switch and light boxes. While doing that, make sure you close off the gaps between box and drywall with insulation, spray foam, or caulking. Noise loves gaps and holes.
Hope that gives you another option,
agreed with the decoupling, which is even more important than the sound dampened drywall. But as a correction, resilient channel only adds 1/2″ and clips + hat channel adds exactly 1 1/2″. Source: Me -from my former and current sound mitigating remodels.
To close gaps with the extended boxes and between floor/wall/and ceiling sections folks should be using ‘caulk saver’ foam cord for larger gaps with acoustic/elastomeric caulk (and just the caulk for very small gaps). Expanding foam shouldn’t be used as that is a hard connection and can couple things you don’t want coupled.
Curtis, where are you located? Do do remediation projects on existing shared walls, in a townhome for example? I’m in the Greenville, SC area.
Terry, adding clips and channel to an existing sheetrock layer would actually make vibration much worse due to triple leaf effect. The existing layer must be removed before applying clips and channel. Check in with Ted White at thesoundproofingcompany.com with any questions. He was one of the original testers during green glue’s development before the product line was sold to Saint Gobain.
Thanks for the information.
What about old buildings with lath and plaster walls?
Your biggest problems with old lath and plaster are: 1) You probably have cobwebs for insulation and 2) The plaster is the consistency of concrete that might have to be drilled before you can screw into it. So just hanging drywall of any type can be a challenge. And tearing it down is usually a horror show. I might give some consideration to putting up Mass Loaded Vinyl, then strapping the walls with 1 x 3, installing 2″ Roxul, then any kind of drywall finish you prefer. If you need great soundproofing, building a room-within-a-room is the answer. I have an article coming out in a couple of days on the subject. You might want to check it out.
Hope that helps,
Adding an air gap between the existing and a new layer will create triple leaf which will turn the sheetrock addition into a drum.
I agree filling the walls with loose fill insulation would help with reducing high frequency echos within the wall. There are many companies that will do blown in insulation as a retrofit.
I don’t know enough about lathe and plaster walls to tell you if there would be an improvement by replacing it with clips+channel+ double sheetrock + green glue. I suggest downloading a sound measuring app to your phone to figure out what frequencies are affecting your space, then compare those frequencies with the charts found on thesoundproofingcompany.com or wherever the article suggested above. I use “audio tool” on android set to 1/12 octave to measure out basement project, although 1/6 octive is probably reaching the limits of my phone’s microphone.
These are completely made up numbers for illustrative purpose only, you would need to measure and look at the actual charts for real numbers.
Lathe and plaster walls might attenuate 40db from 200hz and higher, but due to their rigidity might only attenuate 10db below 200hz. Replacing the lath and plaster with clips+channel and double 5/8 type X sheetrock + green glue might attenuate 40db from 125hzvand higher, but also attenuate 20-30db from 80hz to 125hz, then 10db from 40hz to 80.
So you really need to look at the different frequencies to determine if the wall change would help you.
Two other things I will throw out there is
1. Look at flanking if you are only considering one or two walls.
2. If you need to treat a space with a lathe and plaster or sheetrock on the other side of a wall you opened up, you can add sheetrock with green glue to the back of the other side between the wall studs. I did that in our basement stairwell walls and it works very well.
A member from avsforum.com did a video showing how to do this. Video is a little long of you are just looking for a quick “how to”, just skip forward it is really easy to do.
Thank you for your post-it was very helpful! I’m building an indoor basketball court (50 X 26 ft with 18 ft ceiling) that shares an existing exterior wall with the rest of our home and is on the basement and ground floor level. I’m concerned about reducing the echo and noise inside as well as soundproofing the existing wall shared with our home so that we don’t hear bouncing balls and voices. I am going to use your recommendations of drywall, green glue, and isolation clips to help with noise traveling from the court, but would like your opinion on reducing noise within the court. We will be using a high-impact polypropylene copolymer tile with acoustical underlying on the floor. Any ideas for us? Thank you!
You could try a combination of sound absorbing blankets and acoustic foam panels. USCargoControl makes an 80″ wide x 96″ high heavy blanket with grommets for hanging. Use them on the bottom of the wall from floor to 8′ high. Then I would spot position Little Lucky 2″ acoustic foam panels on the upper portion. You can always add acoustic panels as required, but I think covering about 30% of the wall will diffuse and absorb enough sound to make it acceptable. If you want to get really creative, hang a few sound diffusers on the upper wall also. You may want to look at our article ‘How to Sound Treat a Room‘ for more information.
Hope that helps,
Good article laying out the differences. I would be interested as to your source for your STC ratings in the chart.
For STC ratings go to quietrock.com/products/quietrock-530 Click on Product Data Sheet. For double drywall go to STCratings.com/assemblies.html
The cost calculation for using green glue is notably lower than it should be as your price for a 5 gallon bucket is over $100 less than any GG provider that I can find. It is priced at ~$360 delivered at best. Plus you need an applicator gun which is another ~$75+, something that you need multiple buckets to justify.
So your price of “$250” is actually closer to $425 for a single 5 gallon bucket of GG.
If you happen to have an amazingly cheap supplier please let us know so we can order from them!
I did a quick check and the best price I could find was $314.00 plus the gun at $75.00. Not sure if we made a typo or found a sale that day. But you are correct. Price is closer to $400 than $250.
Sorry for the confusion.
We will be adding drywall to existing walls in a bedroom. We will also be adding Endow window inserts to the windows (storm windows). By doing both we are hoping to get a 10 decibel reduction in sound. My question, is there any benefit to adding QuietRock drywall over the pre-existing drywall Versus standard dry wall? We do feel very slight vibrations in the room. Thank you and my apologies if you already this question. Teresa
Standard 5/8″ drywall with Green Glue sandwiched between the layers will do a good job of adding mass and damping sound. QuietRock is better, specially with Green Glue, but it is three to four times more expensive. I am not sure that the storm windows will do what you want unless they are laminated glass. You could also consider Shut-Eye shutters which reduce noise by 25 – 50 decibels or AcousticCurtain which reduce noise by 21 – 25 decibels, for the windows.
Hope that helps,
We are in duplex and single connect wall with tenant, we wanna make this existing wall sound proof. will you describe the best option for us? and do we need any expert to do this project?
The best way to make the wall soundproof is to build another wall. Please see our article How to Build a Room Within a Room. That will get you as close to totally soundproof as possible. If you want to quiet it down, you can hang sound absorbing blankets or Nicetown soundproof curtains on the wall using self-adhesive hooks instead of curtain rods. Another option is Mass Loaded Vinyl which can be painted. (All of these are available on Amazon.) None of them will make it totally soundproof but will certainly dampen the noise quite a bit. As for needing an expert, it depends on your abilities. If you are fairly handy, you can do most of this yourself–including building a wall. If not, you might want to talk to a contractor or three who have done some soundproofing work.
Hope this helps,
Your article was very insightful and in the last paragraph you state the following:
” If you are serious about stopping the sound, doubling the drywall and adding a viscoelastic material like Green Glue, bump it 8 to 11 STC marks. Now that is sound stopping!’
Before I invest in the drywall, please confirm that two layers of regular drywall sandwiched with green glue is just as effective as the expensive Quietrock?
Also I can’t seem to find the Certain Silent FX drywall anywhere not even Lowes who the manufacturer claims carries it.
Double 5/8″ drywall with Green Glue sandwiched between should be just as effective as one layer of QuietRock. The manufacturer of Silent FX is Certainteed not Certain.
Hope that helps,
Having read your blog and the comments, my question is whats the best solution for me to soundproof my bedroom ceiling, the green glue and drywall? My ceilings are 9 foot so it would be doable. My neighbors living space is directly above my bedroom!
If your ceiling is textured in any way, Green Glue will not work without scraping it down to smooth drywall. The glue has to be in contact with both surfaces to dampen noise. For extra soundproofing you can decouple the new drywall from the existing using either Isolation clips and hat channel, or Resilient channel. If you decouple the ceiling, then install either QuietRock or double 5/8″ dry wall with Green Glue sandwiched between, you should have a more peaceful environment.
Hope that helps,
I plan to knock out the existing drywall that will be replaced by QuietRock wall (530) to block the elevator noise. Could you please tell me what are the right procedures to get the best sound reduction?
Take off the existing drywall, use acoustic caulking to seal any holes and gaps (including the sill plate to the floor, insulate the stud cavities with Roxul 80 rockwool, hang Mass Loaded Vinyl on the bare studs, then install the QuietRock. Should quiet things down quite a bit.
Wow, amazing post. Covers so many unanswered questions I have had from trying to understand how different elements of soundproofing works together.
Would love to get your opinion: with the goal of just dampening adjacent room loud conversation and reasonable TV/music sound, and if we don’t have the ability due to cost/space to do resilient channel, hat clips and such, will doubling up on 5/8” drywall on one side only on the shared wall (but not the other 2 interior walls that open to an open hallway space and other open space) make an appreciable difference?
Or would not doing the non-shared walls negate any benefits of the double drywall? This is steel stud construction which I understand will already offer some improvement over wood studs.
Drywalling one side will be helpful. Adding Green Glue sandwiched between the layers will be even better. Put the new drywall on the noisy side to keep sound inside. You could also consider foam acoustic panels and diffusers in that room to keep the sound in.
After a few days of research, I feel less confident that I can solve my sound/vibration issue without trial and error which isn’t cost effective or a good use of time. I have mechanical equipment (wall mounted on-demand boiler, circ pumps, valves, and enough copper to circle the globe) in the garage with a bedroom on the other side of that common wall. The wall has 5/8 Type-X on the garage side, 2×6 studs, R19 batt, and 1/2” rock on the bedroom side of the wall. In the bedroom, the humming/vibration, and sound is mind numbing when the system is running. I would prefer to leave the existing wall alone as the garage side has most of the equipment mounted to the wall. With that said, I would greatly appreciate your thoughts on how to best tackle this issue. I live in Alaska, where we don’t have companies that specialize in sound proofing. I have in-floor radiant heat buried in 1-1/2” gypcrete floors so nailing into the floor is not advisable (for adding a second wall). A second wall seems to be the best choice but how do I secure it to the ceiling and side walls without the possibility of transferring sound/vibrations? If I use MLV, along with green glue, acoustical caulking, and another layer of 5/8” make enough difference? I believe I can purchase quietrock locally but I will need to verify that next week. Anyway; thanks for any help you can provide. Travis
The second wall is probably your best bet. Here is how I would build it:
Snap a chalk line about 5″ inside the existing wall. This is inside of your new framing. Glue BXI Anti-Vibration Pads @ 16″ on center on the floor (Liquid Nails) and ceiling. Use 3″ drywall screws to hold the ceiling pads in place until glue sets, then remove them. Glue a 2 x 4 sill plate onto the floor pads. Apply glue to the ceiling pads and wedge your top plate in place. When everything is dry install your studs–preferably at each pad location. Cut them about 1/8″ long and tap into place. (Even 1/8″ might be a little long. The pads do not compress very much. Use 3″ deck screws to attach studs. Hammer and nails or a spiker tends to loosen things up.
Insulate with Roxul 80 Soundproofing Rockwool, drywall and finish. Do NOT attach new wall to existing wall in any way. You might want to check out our article How to Build a Soundproof Room Within a Room for a few more ideas.
Hope that helps,
Hi. As everyone else has stated, thank you so much for all the wonderful information. I have the same problem as the last comment above. However, I cannot double drywall the noisy side. Therefore, is the double drywall with the green glue in between still going to do the job on the side where the noise is not coming from.
Yes, it will help quite a bit because of the extra mass and sound dissipation quality of the Green Glue. Noisy side is always better, if possible. But if not, you will still notice a big difference by working on your side of the wall. You can also give some consideration to either Resilient Channel or Isolation Clips and Hat Channel before the new drywall is installed, to decouple the walls. It will add an extra 3/4″ – 2″ to wall thickness.
Thank you for the article.
I was surprised in this paragraph to read, “…screw to the drywall, not the studs…”
Course drywall screws don’t seem to have much holding power in sheetrock–I’m reluctant to hang a sheet of 5/8″ on a ceiling hanging only from gypsum.
Drywall with Green Glue Assemblies
Using Green Glue to damp sound requires two layers of drywall. The first layer of gypsum is attached to the studs. A coating of Green Glue is applied to the second sheet of drywall before it is attached to the first. Offset the seams of the second layer from those of the first, and to screw to the drywall, not the studs. The “glue” is compressed between the two layers and forms a spongy layer that absorbs sound vibrations.
What about new home constructions? I have zero knowledge on home construction and I’m trying to educate myself before undertaking a major project. Cost isn’t an issue with me I value quality and superior performance. I’m looking to sound proof my entire home. I want an exterior thermal boundary with a zip R-12 system with rock wool safe n sound as my interior soundproof insulation. But I don’t know what drywalls, ceilings and floors to use.
It seems like quiet rock alone wouldn’t be enough to address a lot of issue and I don’t have the knowledge behind the science. What would you recommend? I want to prevent sounds between floors and also walls. Oh and I primarily trying to educate myself for future bids on my project. I will be hiring contractors but I want to know and understand what I’m paying for and whether their bid is accurate or overpriced. much thanks in advance
I am a little confused. In the 2nd paragraph you say, “…QuietRock can improve the soundproofing by 15 to 20 points on the STC scale, while it will take up to four sheets of drywall to have the same effect…”
But in your conclusion you say, “…However, the STC improvement between a single layer of regular 5/8” gypsum and the EZ-Snap is only 3 points, which in the world of noise, isn’t much. If you are serious about stopping the sound, doubling the drywall and adding a viscoelastic material like Green Glue, bump it 8 to 11 STC marks…”
You seem to be saying QuietRock is 15 to 20 points better than conventional sheetrock, then later saying it’s only 3 points better. Please help me understand this.
Also, fwiw, I did a price comparison. I could not find a retailer for 5/8″ quietrock so used 1/2″. Lowes, although out of stock, lists 1/2″ QR for $48 with a volume discount. 2 sheets of regular sheetrock is $22. Buying a 5 gal pail of green glue from Amazon makes it $31 per double sheet. So $53 for this sandwich vs $48 for QR.
Great info. Question: I have an office space that has a shared wall. We are looking to convert it to a recording studio. I had an engineer tell me about adding drywall to the existing wall with a gap in between then adding an additional drywall. So not doubled together but doubled with about a 2-3 inch gap in between. Would that significantly decrease sound transmission?
Sounds like he is recommending decoupling the wall, which is one of the best ways to quiet a room. Hopefully he is using resilient channel or isolation clips and hat channel. (Both available at Amazon.) If he uses either product, then double 5/8″ drywall with Green Glue sandwiched between them, it should be awful quiet.
Thanks for such an incredible post. I have a basement suite that I will be renting out, and our baby room and main bedroom are directly above the main room and living room downstairs. I want to try and remove as much airborne noise as possible as voices can be heard pretty clearly between floors.
We have central air, so there’s definitely noise transfer through the vents, as well.
I’ve spoken to several contractors and I’ve been given a few recommendations.
1) cut incisions into the existing ceiling and use spray in foam – I’m hesitant about doing so cause I feel like a lot of gaps could be missed.
2) install carpet upstairs over the hardwood. + Spray in or additional layer of drywall
3) gut the ceiling entirely, lay two layers of roxul, and add 2 layers of 5/8. This is a fair bit out of range for me budget-wise.
4) block off the vents with roxul in conjunction with one of the other methods. We will be installing baseboards anyway, but it’d be preferable to keep the shared heating.
What do you recommend would be the best way to significantly dampen the baby noise without going broke, haha.
Also, do you have any recommendations on how we could reduce noise between the vents without blocking them off entirely or replacing them?
Thanks so much.
1) Do NOT use spray foam. It is great for insulating but not very good at soundproofing. If you can find a contractor to blow loose cellulose insulation in the cavities, you are way better off. All it takes is a small (2″ x 2″) hole in the drywall, a long hose, and someone who knows how to turn the air down and patiently fill the cavity. You can do it yourself by buying the product from Home Depot or Lowes, and renting a machine from them.
2) Installing heavy wool carpet will help a lot. For extra soundproofing install QuietWalk Plus (Amazon) first. See our article Best Soundproof Underlayment.
3) If you add the carpet upstairs, you should be able to just add one layer of 5/8″ drywall with Green Glue sandwiched between the old and the new. (Existing drywall needs to be smooth–not textured for Green Glue to work properly.)
4) Blocking off vents is NEVER a good idea. It can overload your heating system, shorten its lifespan, and possibly cause a fire. If you can position heavy furniture or book cases over, or in front of the upstairs vents and still allow air movement, that will absorb and deflect some of the sound.
Hope that is helpful,
Thank you for the informative article. I learned a lot.
I read on the Quietrock website their suggestion to add their version of Greenglue (Quietglue Pro) between the Quietrock and an existing drywall for an additional 3 STC. Does that make sense to you? If so, would using Greenglue compound be more effective than Quietglue Pro.
Sorry, I do not know anything about Quietglue Pro. If I were to guess, it is probably much the same as Green Glue, otherwise they would not advertise it. Green Glue has been the most used product for years–because it works as claimed.
Thanks for the great article.
I have a first floor “home office” space that I would like to better sound deaden. Currently the “noise” comes from the ceiling above from family members walking on the hard wood floors that do have rugs (my house is 3 stories with the office located on the first level) and the second place where the sound comes through is one wall. The existing ceiling does have a light texture on it as well as two hfac vents, one ceiling fan and two recessed light fixtures. The wall that also has a light texture on the drywall.
Would you suggest sanding the drywall and adding an additional layer of drywall to the ceiling with green glue in between the drywall? The same with the wall?
Thanks very much
I assume it is not popcorn texture that just scrapes off. Sanding a ceiling is not much fun. You might want to give some consideration to 5/8″ QuietRock. QuietRock is made of 2 layers of drywall with a viscoelastic polymer sandwiched between them which performs like Green Glue. (For more information see this Wikipedia article.) If the ceiling is fairly smooth this should work. If not, you could strap it with 1 x 2, or for extra decoupling use Resilient Channel.
Want to soundproof the outside of a wall next to a busy intersection, where acceleration noises are very high. Now there is only a “thin” decorative panel over 6″ wall studs with fiberglass insulation. What about 1/2″ OSB with painted cuts and surfaces for water proofing, nailed directly to studs, green glue MLV to that, then green glue decorative panel to MLV and offset-screw decorative panel into OSB? Will it reduce the noise significantly, or are there better alternatives, keeping in mind I want to keep the cost low and the wall and windows to look like the original as much as I can..
I am not sure what your decorative panel is, but it sounds like you are removing and replacing it, so it has to be somewhat waterproof. To get the best results from Green Glue, it has to be between 2 rigid surfaces. I suggest that once the decorative panel is off, install the MLV directly to the studs. Then the OSB (3/4″ is better if possible). Then Green Glue and you panels–assuming they are rigid.
Another option, if you are concerned about waterproofing is MLV to studs, 3/8″ OSB, Green Glue, another layer of 3/8 OSB to make the Green Glue sandwich, then tar paper or house wrap, and finally your decorative panels. I would do it this way because it is only 1/4″ thicker than your original 1/2″ OSB and gives you best soundproofing and waterproofing.
Hope that makes sense,
Thanks for doing the research on this topic. I have an existing wall dividing a side by side duplex. I am fortunately am able to add up 1 1/2″ of thickness on one side and I really want to reduce the sound for both sides since I own the building. It is currently 2×4 studs with R13 in between and 5/8″ drywall both sides. Would a Green glue 1/2″ drywall green glue 1/2″ drywall (2 layers) provide a much higher noise reduction than just one 5/8″ drywall green glue sandwich. What results would you anticipate/
And thank you for warning me off the Styrofoam drywall sandwich idea.
Hi Terry. Great info. Sorry if the following question has already been been answered:
If I double drywall with the green glue, can I still hang heavy things like shelves/cabinets (which will need to be anchored to studs by screwing through both layers of drywall)? How will that affect the soundproofing? Also, you mentioned not to screw the second drywall to the first using the stud. How do you recommend fastening the 2nd layer of drywall to the first?
Hello – Thank you for all this insight. We have a scenario similar to Datis above and trying to contain the sound of media room with in ceiling speakers going into our basement which is directly below our sunken floor family area. We want to be able to keep in the noise (including bass) in the basement but only have 7ft from joint to concrete floor to work with in the basement. Thus, we only have maybe 2inches to work with between flooring going in to fit the planned screen and cabinet before hitting the ceiling.
Our GC had mentioned putting in two layers of cork but AV guy says that won’t get bass noise. AV guy suggested QuietRock and channels but we don’t have space to do hat channel. Should we do double drywall and greenglue up to the subfloor (term??) up above in between the joists, then RockWool (Safe and Sound?) and then QuietRock? Or would we get same value of one layer QuietRock in between joists, Rockwool and then regular drywall? Some other combo?
GC is new to greenglue and QuietRock but want to see what would get us the best bang and fit in the limited vertical space. Is cork in any combination of value in this scenario? Trying to figure what we can order and get in place with them in the midst of framing now as we adjust course a bit.
I wish I’d stumbled on this article sooner, would hve saved me six months of research!
I have an office/home theatre/edit suite in the basement and started to wrap the whole room in mlv. 2lb on the walls (2×3 wood studs with r5 rigid insulation in between, leaving an airflow gap against the concrete) and 1lb on the ceiling, but unfortubately the old house uses joist space as cold air return ducting, so no batts. . Ive built mdf backing boxes lined with 5/8x and green glue, and sealed the seams with green glue acoustic sealant and tuck tape. The ceiling joists are only 7.5′ high. My plan was to use green glue brand clips (lower profile than Platiq brand) and hang double 5/8x with green glue. Could i get away with just one layer of ez snap?? It’s a busy livingroom upstairs, and at the same time those 14″ subwoofers liketo be heard inside the room, but not upstairs.
Bottom line is it’s a small 11’x20’x7.5′ room, so the less material to save room space the better. Would ez snap do the same as that 2x 5/8 solution?
This was an excellent article, i found my way here from a large canadian drywall supplier (i guess i was asking too many tough question 😁)
I would try the single 5/8″ EZ Snap. It should be pretty close to enough. It already has the viscoelastic inside that you get from Green Glue. One of the advantages of putting on one layer of EZ Snap, is you can live with it for a day or two–trying all the different things that make noise. See what it sounds like. If you have to add another layer of standard 5/8″ with Green Glue, you have lost nothing but a day or two.
Sorry to hear about your drywall supplier. Must be from Ontario–says the native Albertan. We NEVER have trouble out here.
Terry, the article was extremely helpful and the comments section is equally valuable.
I have an apartment above me that has wood floors. The squeaky floors above and a bit of conversation noise is what is most annoying.
My ceiling has 2″ x 6″ joists with R-19 insulation and 1/2″ drywall. My plan is to layer 5/8″ drywall onto the 1/2″ drywall ceiling with Green Glue compound layered in between. The ceiling also has, however, 6″ diameter recessed can lights about every 6′, for a total of about 8 lights. Will the openings for these can lights negate the benefit for the 5/8″ drywall and Green Glue? Thoughts on how best to address the can light situation without removing them completely?
It would be real nice if you could remove the pot from the ceiling mount without damaging the drywall, drape a piece of fireproof rockwool over the top, then replace it. I an guessing the top of the pot is pretty close to the floor above. Getting some soundproofing between the floor and the top of your pots would be a good thing. Because all those little cans will act like speakers. Pot lights can get pretty hot with incandescent bulbs in them. Acoustic caulking between the can and new drywall will seal that gap. If you do not have a ring on the light to conceal the caulking, use a painter’s caulk. Acoustic caulking never dries, and is usually black, so covering it is kind of necessary. Painter’s caulking will dry out and look better, but because it is hard, it transfers noise easier.
Hope that helps,
I want to soundproof two bathroom walls in a master suite…one wall (10 running feet) separates the master bath from the guest bedroom, and the other wall (8 running feet) seperates the master bath from the guest bath.
The two adjacent rooms are completed and cannot be made better than what they are: The guest bedroom has 1/2″ sheetrock their side of a 2×4 wall, and the guest bath has 1/2″ sheetrock on their side of the top two-thirds of the 2×6 wall, and 1/2″ cement board and marble tile on the bottom third. In addition it is punctured by an in-wall medicine cabinet and a niche in the shower.
In the new bath room the wall adjacent to the guest bedroom is slated to have wood wainscot on the bottom third and sheetrock on the top two thirds. The wall adjacent to the guest bath will have stone or tile for where the shower enclosure will be…approximately five running feet of wall…and the remaining three running feet will be wood wainscot on the bottom and sheetrock on the top. I have about 2 1/2″ of space that I can afford between the face of framing and the finish surfaces and have the clearances I need for the toilet. I’m wondering what is the best use of that 2 1/2″ for maximum noise reduction.
I was thinking clips and channel, and two layers of 5/8 w/greenglue, and in the areas with wainscot or tile, just one layer of 5/8. Would It be worth it to go with two layers of QuietRock where possible and a single layer of quiterock topped with the wainscot or tile where applicable?
If you use isolation clips and hat channel, I do not think that you will have enough room for double 5/8″ drywall. Clips and channel are going to eat up about 1 1/2″ of space. Why not forget the clips and channel and hang 1 lb. Mass Loaded Vinyl (STC 27) on the studs, then double 5/8″ with Green Glue sandwiched between. Should be more than enough to keep the bathroom sounds where they belong.
I have a duplex party wall that I am trying to redo. No tenants yet, so I can work on both sides. Currently has R-13 fiberglass insulation, one 2×4 wall, and sound board on one side. 1/2 inch drywall. I can hear talking pretty plainly. I don’t think I have room to add another 2×4 wall with space in between. Windows are in place and only have three inches from the wall to the window. What would you do? Party wall is 22 feet long. Would replacing insulation with rockwool safe and sound be of an advantage? Adding 5/8 drywall with green glue? Sound board barrier on the side that doesn’t have it?
Hi K B,
If your studs are open on one side, get some Mass Loaded Vinyl and hang it on the open stud. MLV absorbs sound and has an STC of 23 by itself. Then you can add double 5/8″ drywall with Green Glue, or QuietRock. You can also replace the fiberglass with with Roxul, but I think that the MLV, double drywall/Green Glue or QuietRock will do the trick without the expense.
Hi…thanks for all the help on sound. We are creating a rehearsal space for the kids and currently have wall assemblies with 1/2″ drywall – 1/2″ firebreak fiber board-wood studs-batt insulation-1/2″ drywall. Because those are already pretty thick I’m going back and forth between 5/8″ or 1/2″ QuietRock. We are also building a 2nd room with same configuration except the wall used to be an exterior 5/8″ shiplap type exterior wall (must have been a room addition. But same question, do you think 1/2″ is good enough to raise the STC ratings in order to drop the dB ratings of heavy metal (think Metallica at 90 db+) AND would you recommend Green Glue between the QuietRock and the existing wallboards? Thanks and I’ll take your comments off the air……(long day 🙂
If at all possible use 5/8″ instead of half inch. Does not sound like much but the extra 1/8th inch adds 25% to the mass of 1/2″. I would use Green Glue. It will absorb and dissipate an extra layer of noise. (And Metallica at any decibel level is unacceptable. If AC/DC or Led Zep, that is a different story.)
I have a “private club” in my three car garage. The sound level inside is considerable. 105dB slow C on the center of the dance floor. Bass, of course, is the issue.
Initial concern was garage doors. They were replaced with high quality insulated doors with weather seals all around. Additionally, I built 2” thick 4×8 panels of T111 and filled with 2” Owens 703. These are decoupled from the doors and reduce bass considerably.
Sealed all “eaves” with caulking and covered vents with plywood.
One side wall of garage single 5/8 drywall with “stucco” exterior and is 35dB down on dance floor. The other side, closer to dance floor, is single layer 5/8 drywall and T111 exterior. This side also has a 3’x6’ window that has been filled and sealed with plywood and 2” Owens 703. This side is only 20dB down. It’s my weak spot. The wall, not just the window, vibrates. This wall is 8’ tall and 20’ long.
So I am considering a few “ideas”.
Note: window will be covered by all ideas.
1) add foam/stucco layer to interior of wall with “plaster finish”
2) add two to four layers of 5/8 drywall with green glue between to existing interior drywall.
3) add a single layer of “Quiet Rock 545” to interior drywall.
4) possible with each of these – remove existing interior drywall and add additional studs 1.5” deep to “decouple” the new layer of one of the choices (1-3) above.
Since bass (35-100) reduction is the goal, STC ratings are pretty useless to me.
Which would you choose? Other ideas? I’m leaning towards decoupled Quiet Rock 545.
I would also go with decoupling. You might want to give some consideration to leaving your drywall alone and adding either resilient channels or isolation clips and hat channel. You may want to take a look at How to Build a Soundproof Room Within a Room. Also, if you have not already done it, add serious Bass Traps to all 8 corners. You might want to check out How to Keep Bass from Going Through Walls and 18 Ideas and Plans on How to Build DIY Bass Traps.
Thank you for the article it is very informative. My question is will green glue sandwiched between existing 1/2” drywall and new 5/8” drywall be effective if studs are only 16 apart? I read somewhere that green glue is really only worth its money when the studs are 24 apart. Is that accurate? I have a party wall with no access currently to noisy side so was going to double up the drywall on my side with green glue in between but would rather not drop the extra 500 for the GG if it won’t help.
Green Glue works on points of resonance. So it will work better on studs that are 24″ on center. It will work very well on studs 16″ on center also. Keep in mind that you have to wait 7 days to get the full effect of Green Glue. Many people miss that part of the instructions.
I have a party wall that is allowing the neighbors tv bass to come through. It’s quite disturbing. Is there anything you’d suggest? I was thinking mlv with quietrock. I would liquid nail it vs drilling to have it completely sealed over the existing drywall.
MLV and QuietRock should help quite a bit. But as much as I like Liquid Nails or PL400, I would have a lot more faith in the drywall staying there if it had a few screws in it. You might also want to look at our article How to Keep Bass From Going Through Walls for a few more ideas.
Thank you for this informations about soundproofing. I have a question.
I want to know what STC I will have with a smartsound pannel, a resilient bar and two 5/8 gypse with green glue ?
And if I have the soundsmart panel with ez snap qietrock ?
Depending on the type of wall (2 x 4 or 2 x 6, brick or concrete block) and what type of insulation you have, I think you could have an STC over 50.
Thank you for great article and the amazing comment section!
I’m remodeling an apartment in a building form 1901. We removed the old plater ceiling to add soundproofing. At the moment you can literally look up into the upstairs unit through some cracks of the neighbor’s floorboards.
We also installed some DMF OneFrame cans (led lighting) which suppose to have good STC ratings, so hopefully they won’t make it too much worse.
The contractor suggested to install one layer of QuietRock, but we are not sure if that’s enough or if 2 layers of regular 5/8 with green glue would be better for the ceiling?
Do people use resilient channels or clips with just one layer of QuietRock or does that not make sense?
What would you recommend to get good sound proofing without being able to touch the floor above?
Install Roxul rockwool soundproofing insulation between the joists to absorb noise. Then I would install 2 layers of 5/8″ drywall with Green Glue sandwiched between them. You can use resilient channel or isolation clips and hat channel if you like. But you will lose between 3 and 4 inches of head room in total.
I would have a bit of an argument with your contractor because his suggestion exchanges one type of soundproofing for another. The 4 types of soundproofing are:
Absorption. Roxul rockwool insulation
Dampening. Green Glue or QuietRock.
Mass. Double 5/8″ drywall.
Decoupling. Resilient Channel or Isolation clips and hat channel.
I really appreciate the article and information. I was thinking of just doubling the standard drywall but someone suggested quietrock for the 2nd layer to improve the sound reduction even more. Do you think it would make a significant difference to justify the higher price?
Can you comment on the outgassing of Greenville and quiet rock? Are they products that can be used where indoor air quality is a concern? Do they have an odor?
Great article–thank you. I was wondering what the pros/cons of using Quiet Rock AND Green Glue together. Would that get better sound dampening than either of them individually? And would you recommend that on a ceiling?
Does this quote compare equal thicknesses of QuietRock vs drywall? Is it comparing the 5/8″ or even 1&3/8″ versions of QuietRock vs 1/2″ drywall?
“QuietRock can improve the soundproofing by 15 to 20 points on the STC scale, while it will take up to four sheets of drywall to have the same effect.”
Terry- ceteris parabis otherwise your thoughts on dense packcellulose versus rockwool 80? Comparable sound absorption? Some claim fiberglass bats, at far less expense, come close to rockwool for this purposes as well ?
Also sounds like the biggest bang for money is decoupling two sides of the wall, regardless of drywall, insulation etc. (i.e., vertical 2×4 studs staggered on 2x 6 sill plates