Decoupling Explained

[For a quick and basic understanding of sound proofing please read our soundproofing 101 article first.]

During your research on the topic of soundproofing, you have almost certainly come across the term decoupling. Decoupling means mechanically separating the two sides of a wall to make it harder for sound to pass through the wall. Here is a simple example of decoupling two sheets of drywall.

Here we show a simple sketch of how wood studs couple the conventional wall, and how products like resilient channel or resilient sound clips can decouple it and improve performance.

The stiffness of wood studs couples the two sides of a conventional wall. As a result, sound can easily pass from one side, through the studs, to the other side.

Sound can pass through this type of wall without going through the air and the insulation, so insulation has only a limited effect on the single wood stud wall.

By including a resilient decoupling mount, the sound that tries to pass to the other side via the structure is thwarted, and performance can improve.

Because sound cannot easily pass through the structure, it has to pass through the air cavity, and insulation becomes far, far more effective.

Part 2 – Decoupling and Resonance

When you move two sheets of drywall apart you do improve things, but only at some frequencies.

What happens is that the air in the cavity of the decoupled wall acts like a spring, and like all mass-on-a-spring systems, this results in a resonance. At (and around) this resonance point, the performance of the decoupled wall is actually considerably worse than if no decoupling had been used. Like this:

In theory (and in lab tests and in the field), decoupling only helps well above the low frequency resonance. In this case, with a resonance of 63 Hz, the decoupling only helps above 100 Hz, and hurts performance below this frequency. Let’s take a look at an actual lab test exactly as above.

One of the lines to the left is 4 layers of 1/2” drywall as a solid slab with no air cavity.

The other line is the same drywall, but with 2 layers on each side of a 2x4 wall with resilient channel and insulation.

As predicted above, what we observe is large gains at higher frequencies, but performance losses at lower frequencies.

This is caused by the resonance intrinsic to decoupled walls. To attain both the tremendous high frequency performance of decoupling and good low frequency performance, we will have to address this resonance problem somehow.

Attaining good low frequency performance: Part 1 - Lowering resonance frequency

To attain good low frequency isolation with a decoupled partition, we will have to handle the resonance somehow. The first method that we can use is to cause the wall to resonate at lower frequencies. To do this we have to:

a) Add mass to one or both sides of the wall e.g. another layer of drywall (heavier decoupled walls have lower resonance frequencies).

b) Increase the depth of the air cavity.

c) Add insulation (if no insulation is currently present).

The benefits of lowering resonance are two-fold:

1) The frequency range where the wall performs poorly moves down
to frequencies that the human ear can’t hear as well, which reduces disturbance.

2) The frequency range where the decoupling is effective becomes
wider – your decoupling efforts work on the lower frequencies as well.

Notice how, as the frequency of resonance goes down, performance at frequencies important to theater, music, traffic, aircraft, and the human ear are greatly improved.

It’s a lot better to have a 20 Hz problem than a 40 Hz problem, or to have a 40 Hz problem than an 80 Hz problem!

If  your resonance is high in frequency, your decoupling efforts may make things WORSE, not better. For example, you would be better off for almost any application to use two layers of drywall sandwiched tightly together than you would to use two layers of drywall separated by one inch.

Later in this document we will go over some basic tips for lowering resonance and attaining good all-around performance. Next, we’ll look at our other option for dealing with resonance – damping it with viscoelastic materials.

Attaining good low frequency performance: Part 2 - Viscoelastic damping


We saw above that conventional decoupled systems have considerable performance dips at resonance. It has been demonstrated in lab tests that products like Green Glue, have a substantial positive effect at resonance on conventional, coupled walls. The same benefits are observed to the same extent on decoupled walls such as double stud walls. By an enormous margin, pound for pound the best wall that you can build is a visco-elastically (e.g. Green Glue) damped double stud wall.

Table – choosing the right decoupling system for low frequency performance.

Best decoupling
selections for walls

For conventional (non-damped) drywall

For well damped drywall (such as Green Glue damped board)

Best type of decoupling

Double stud wall

Double stud wall

2nd best

Modern sound clips like Whisper Clip

Staggered studs

3rd best

Staggered studs

Sound clips

4th best

Resilient channel

Wood or metal furring channel (not resilient)

5th best

Wood or metal furring channel (not resilient) perpendicular to the studs at 24” on-center

Resilient channel

Best decoupling selections for floor/ceiling constructions

For conventional (non-damped) drywall

For well damped drywall (such as Green Glue damped board)

Best type of decoupling

Separate ceiling joists (true room within a room)

Separate ceiling joists (true room within a room)

2nd best

Modern sound clips

Sound clips

3rd best

Resilient channel

Resilient channel or non-resilient
wood or metal furring


Tips that are invaluable when planning a decoupled partition:

1. Use as much mass as possible on each side of the wall.
2. Always use double drywall on at least one side of the wall.
3. Use as deep an air space as possible.
4. Use insulation. Fluffy fiberglass insulation is as good as anything.
5. Select modern sound clips such as Whisper Clip over resilient channel (lower resonance point).
6. Select double stud walls over anything (lowest resonance point).
7. Use Green Glue damping compound.
8. Choose thicker, heavier drywall over thinner – i.e., use all 5/8” drywall if possible

Construction diagrams

These should be helpful to anybody wondering what, for example, a double stud wall is.

Conventional wall (coupled)

Staggered stud wall. Shown
is 2x4 studs offset on a
2x6 base plate

Double stud walls. Two
separate rows of studs with
drywall only on the outside

Resilient Channel

Resilient channel (see image to the right) is a thin, flexible metal channel that is screwed to the studs. Drywall is then screwed to the channel, and the flexibility of the channel creates a decoupled wall.

Sound Clip

Sound clips are typically rubber-containing devices that screw into the studs of your wall. A Metal Hat Channel is then inserted into the clips, and drywall is screwed into the Hat Channel. These clips provide decoupling by virtue of the resilient rubber component of the clips that ultimately supports the weight of the drywall. Product featured in image to the right is our popular TMS Silent Clip - A237R.

Alternative sound clip options, like the Whisper Clips featured on our soundproofing site, provide resiliency through their distinct design contributing a higher rating than their rubber counterparts.

Silent Clip with Hat Channel Installed on Wooden Stud and Drywall System




Decoupling is an extremely powerful tool, and can raise the STC extremely efficiently. Ultimately, every truly great sound isolation scheme will utilize some type of decoupling.
However, decoupling is not effective at all frequencies. In fact, decoupling a wall results in reduced low frequency performance around its resonance point, and is only effective at frequencies much higher than resonance. Thus, to lower the frequency where wall performance is weak and maximize the frequency range over which decoupling helps you, you should strive to have resonance as low as possible.
The combination of viscoelastic damping and decoupling is extremely potent – giving the benefits of decoupling without the drawbacks.

Click here to see our Soundproofing Materials.

Customers Questions and Answers

1) Ernest: Hello, I currently live in a townhouse (in Canada), with one shared wall, including one side of our master bedroom. On occasion, we can hear our neighbours talking in the next room (very faint mumbling, but we cannot make out what they are saying). We also hear heavy footsteps on the rare occasion. I had a local contractor come do an assessment. When we drilled a hole, we found fiberglass as insulation between the concrete wall and drwall. We took a look at the attic and found that there was a sheet drywall separating our units. From a building code perspective, I would assume that the concrete wall goes all the way to the roof. The insulation in our roof is also fiberglass. The contractor suggested adding a 5/8 in drywall with Green Glue for the shared wall. He also suggested adding cellulose to the roof. With regards to the thumping and lower frequencies, I would like to know if there is merit to decouple the roof with sound clips? I am also open to any suggestions you may have to make the optimal mitigation strategy. Thanks, Ernest

Trademark Soundproofing Reply:

Hi. I don't believe decoupling the ceiling will help with the thumping noise that is coming from the side, which is mostly coming through the floor. If anything I would decouple the wall first.

2) Anne: Hi there, I live in a converted 1930s factory building that has almost no insulation between floors vertically: The floorboards of one apartment (1" spruce board) rest on 12" joists, and then a tin ceiling is nailed directly into the joists. Other than dust, there's nothing in the way of insulation. I am planning to take down the tin and insulate somehow, and wonder whether I should add insulation of some kind and then decoupling clips before ranging the tin. The sounds that come through are TV, conversation, etc., and footsteps when people are thumping around up there, though that seems to be less of a problem. Anything would be better than this (though my neighbors are nice!) but I'd like to do it once, right. I've considered using a layer of green glue on sheetrock strips which I wedge in between the joists up against the spruce boards, and then hanging the tin from resilient channel. Does this seem like a workable plan? Thank you!

Trademark Soundproofing Reply: Hi Anne, Definetly add the insulation. I would suggest that you add a layer of drywall to the clips and channels and then install the tin onto that. If you really want to beef it up, add 2 layers of drywall with Green Glue in between to the clips and channels first.

3) david f: Hi guys. I have a question that is driving me mad please could you help!. I am building a soundproof garden studio this summer. I have the wall solution ticked (Room within room - double walls), the ceiling ticked (floating joists on top of the inner wall between outer wall joists), Double skin of inner plaster board with Green glue inbeteen.. However, I am perplexed with the floor!!. My building is going to be built on a floating wooded base which the Outer AND inner walls are to be attached to. So, yes, if the sound hits the walls and ceiling it is fine. It also cannot flank through the ceiling or up the upright edges.. it can however flank into the floor, under the inner wall, and up through the outer wall. Could someone kindly advise a solution?. Thanks so much.. it is driving me mad! :) Many thanks David

Trademark Soundproofing Reply:

Hi David. You can build a floating floor using the Rubber Joist Isolaters. Fill with fiberglass between joists. and use 2 layers of subflooring with Green Glue in between. Thank You.

4) Pam: I live in a single level condo. I share a crawl space and attic with the unit I have a common wall with. Our current solution is to remove my current drywall and add new Roxul Insulation -> Hang Mass Loaded Vinyl (1 lb) -> Decoupling clips and rails ->5/8 drywall -> Acoustical caulk at seams -> green glue -> 5/8 drywall. And we are insulating the outlets on both sides. I'm good with this solution, but... we discovered today that I also share a sub-floor with this neighbor. They recently installed new carpet and now I can hear the TV more. In addition, when they had their TV on the shared wall, I could clearly hear it. My question... Will the shared sub-floor cancel out or seriously compromise the effort put into soundproofing the wall. I have hardwood floors nailed onto the sub-floor, no padding, no floating. I am not concerned with structural sounds, I'm very concerned with TV and stereo. Thank you!

Trademark Soundproofing Reply:

Hi Pam, the wall build is excellent however I see a problem with noise coming over the wall via the attic/crawl space. You would have to add another layer of drywall with Green Glue to your ceiling as well. Sharing sub floors is a common problem and not much you can do about it at this point.

5) Alexandre : Hello, We just bought a 1600 sq feet condo in a beautiful historical building constructed in 1905. Unfortately, it needs serious soundproofing. We can hear every footsteps of the upstairs neighbours: both the impact sound and the very loud squeeky hardwood floor. We can't hear uptairs TV, music or conversation, though. We can't sleep at night and this is affecting our health. What soundproofing solution would you recommend? Regards, Joseph

Trademark Soundproofing Reply:

Hi, Joseph, Please see this article

6) Craig: Hello, I am looking to decouple the walls in a home theatre room but would like to know how should I reattach the skirting & architraves to the walls without compromising the sound insulation. I intend to use furing channel and whisper clips. Thanks Craig

Trademark Soundproofing Reply: Hi Craig. Those can be attached through the drywall into the hat channel. Just be sure to attach clips and channel at the heights you will need for the baseboard and mouldings.

7) Lorrie: I have noise from a diesel truck starting up very early in the morning not far from my bedroom. Sometimes the truck is started and let to run for some time. I have one window on that side of my bedroom and a glass sliding door on another wall. I am wondering about a metal rolling shutter with an STC rating of 59for the window and adding insulation to the outside wall around the window. I am also considering taking out the window and increasing the insulation in the wall. Would any of these ideas make sense for soundproofing. I sleep with earplugs and a white noise machine, but I can still hear the truck in the very early hours in the morning and I am becoming sleep deprived.

Trademark Soundproofing Reply:

Hi Lorrie. Yes your ideas make sense. Doors and windows are weak links and removing them and replacing them with a solid wall is much better. You can consider using our removable window soundproof panel and our soundproof door panel. Keep in mind that sound may still be leaking through the walls however you are best of treating the window and wall first (I am also a bit skeptical that the shutter can achieve an STC rating of 59).

8) Marshall M: I have 2 conference rooms that share a common wall. I need to isolate the wall to mitigate sound from each room. The wall is 10ft H x 14ft W, 3 5/8 metal studs, under 1 layer of 5/8'' sheetrock each side. Suggestions for sound proofing system? Would it be more efficient to leave existing wall and frame new decoupled wall next to existing. If so, could i flat stud the new wall to save burning floor space and still achieve a good sound barrier? I need to perform the work from 1 side only, I don't have access to the other side of the existing wall.

Trademark Soundproofing Reply:

Hi Marshall, If you leave the existing wall you will be running into an issue called the triple leaf effect. better to remove the existing drywall, use resilient sound clips and hat channel to decouple and save space. Put 2 layers of drywall onto the channels. If you have a drop ceiling with open space above the wall you would need to treat your ceiling as well.

9) Peter: I am trying to convert an existing garage into a music studio for a reasonably loud band - the garage is completely separate from the house, has aluminium siding with heat insulation and has been finished on the inside with stud walls and a single layer of drywall. I was planning to build a room-in-a-room but your articles have me worried about the triple-leaf effect. I could tear down the existing drywall but that would only leave insulation and aluminium on the outer wall - What do you suggest?

Trademark Soundproofing Reply: Hi Peter. If you move the room within a room far enough from the existing wall (at least 12") you should be OK.

10) Ewa T: Hi We are working on the sound sensitive building and get the recommendation to decouple exterior sheathing. Please advice if we can achieve it with any of your products. It would be the best if we can email wall structure sketch. Thank you

Trademark Soundproofing Reply: Hi Ewa. Yes it can be achieved with some of our products. Please email your sketches to Thank you.

11) Mayumi: Hey there, will decoupling a wall help with high pitch? I have a cockatoo... Presently I am thinking of Roxul insulation, decoupling drywall, green glue with another layer of drywall... Should I also add a layer of vinyl? Thanks.

Trademark Soundproofing Reply: Yes it will help. If you are using 2 layers of drywall on the clip s and channel you can get away without using vinyl.

12) Kevin: Hi! I'm building a studio addition on my house, and it's built with room-within-room construction over a concrete slab. My question is if resilient channel is needed if I'm building dual walls and dual ceilings. The designer shows resilient channel, but I'm starting to think that the gain may not be worth the effort. Dual 5/8" Sheetrock w/ green glue for all interior walls and both interior and exterior ceilings. The exterior walls of the addition have 4 layers of 5/8" Sheetrock. Thanks for any advice.

Trademark Soundproofing Reply:

If you have a complete room within a room and the inner walls and ceilings are not connected with the outer ones than you can get away without using resilient sound clips and resilient channels. Double drywall with Green Glue in between is a great idea.

13) Jeff: I have a two family home built in the 1890s and i live on the top floor. There are hardwood floors upstairs and there is significant footfall noise downstairs. Would it be sufficient to add green glue and a second layer of 5/8 inch drywall to the ceiling and walls downstairs? If not, what else would I need to do?

Trademark Soundproofing Reply:

Not really. You would need to remove the drywall. Install insulation, resilient sound clips, hat channel, drywall, Green Glue, drywall.

14) larry r: would it not help to put green glue on the studs then attach the first sheet of drywall? Also is it ok to install first rock vertically and the second sheet horizontally? Thank You

Trademark Soundproofing Reply:

It would help very little. Rather use the Joist Gasket Tape. Yes you can install the 2 sheets in different directions.

15) Frank: Simple question that can't seem to find an answer. I am completing my sound room. 2 wall are underground 12 block, 3 inches spray high density foam for temp control 3 inches wood frame for air gap, 5/8 inch drywall, greenglue, 1/2 inch drywall. Remaining two walls are decoupled double wood frame wall with a small gap (limited room for more),1/2 drywall on outside, 5/8 inch drywall, greenglue, 1/2 inch drywall on inside, each framed wall is filled with roxul. The ceiling is the question. Ceiling joists are 16 inch on center with 9 inch cavity. What is best option, 3x3inch roxul to fill cavity, 2x3inch with 3 inch gap between, 6 inch roxul with 3 inch air gap at top (Floor side), or 3 inch roxul with 6 inch air gap on floor side?? The ceiling is finished for 5/8 drywall, greenglue, 1/2 inch drywall. The air gap is the question. I am also considering RC and or MLV before the drywall. Interior of envelope contains an isolation booth and control room with single stud wall with roxul and 5/8 drywall, greenglue, 1/2 inch drywall on both sides facing interior of envelope. Not sure where diminishing return is not worth cost. Thanks in advance Frank

Trademark Soundproofing Reply: We recommend filling the air gap wit regular fiberglass or mineral wool insulation without compressing it. So if you have a 9" area between your joists you can fill with 9 inch thick (or the closest to that) insulation.

16) Frank: Great, that is what I have and was planing to do. I just could not find anything that stated that specifically, just info on insuring an air space. Just a side note, I understand you don't have any hat channel, and may not be able to get any by the day of the month. Any suggestions of another effective product from you or someone else? Otherwise I will have to build a substandard structure based on what I wanted to do.

Trademark Soundproofing Reply:

Hi Frank. We should have plenty of hat channels, as that is a stock item. We may sometimes run short when many orders come in at once however we are usually restock within a few days.

17) Mridul A: Hi, pl confirm if the following solution will work to soundproof and acoustically treat a 11X9 ft room. a) Adding Mass on the brickwall (directly pasting/bolting mass loaded vinyl). b) Then mounting a wooden frame of 50mm right on this. c) Filling the frame completely with Rockwool (50mm). d) Covering all the rockwool inside the frame with a plyboard. e) And, finally pasting acoustic foam all over the plyboard with bass traps on the 4 corners. Pl confirm if I need to make any changes in this. regards Mridul Aggarwal

Trademark Soundproofing Reply:

Change (b) to mount the wooden frame half inch off the brick wall. Change (d) to add a 2nd layer of plyboard with the Green Glue Damping Compound in between the 2 boards.

18) Stuart Welch: I have a 1970's era 1st floor condo. There is one unit above us. Current construction: 2" x 8" joists (ceiling for me - floor for them) x 16" centers. Fiberglass batt insulation is in the gap. Ceiling drywall is 5/8" Type X. Original installation included "isolation clips" between my ceiling drywall and the joists. However, they are screwed directly from drywall to joists. Footfall and typical chair move across floor in unit above is what I want to abate. I have spent a lot of time on your site researching. Is the best solution isolation clips, channel and drywall screwed to that? With the "new" 1 5/8" gap provided by the clips and channel, should I add a 1" insulation batt (suggestion on type please) before installing drywall? Or, is my best bet just another layer of drywall with green glue? Or, that plus clips/channel/drywall? By the way, great site and resources and information - I've learned a lot.

Trademark Soundproofing Reply:

Hi Stuart. If you do that to the original drywall you will be creating the triple leaf effect, something we want to avoid. You are best off removing the existing ceiling drywall and starting over with proper resilient sound clips, channels, double drywall with Green Glue. Your welcome. Glad that our hard work is enjoyed and appreciated.

19) Jon L: Hi there. I am working on a soundproofing project, and I am going to use a double drywall with greenglue, on a double studded, staggered wall. My question is that if I mount something heavy to the studs (a 5x guitar rack) will i negate my green glue installation?

Trademark Soundproofing Reply: Hi Jon. Green Glue is a damping compound and will not be negated by anything mounted to . A decoupling method would be the place to worry about it and only if your mounting went through to both studs of the decoupled wall.

20) Justin A: Hi! I am building a detached garage for a rehearsal space. I built the frame with offset 2x4 studs on a 2x6 plate. My question is about insulation. A standard piece of R-13 which is 3.5" thick will be compressed against the offset stud holding up the opposite wall when pushed into the cavity. Will the compressed insulation negate the effort of offset studs? I will be using 1/2" and 5/8" double drywall with green glue for the interior walls. Exterior is 1/2" particle board and hardie siding. Thanks, Justin

Trademark Soundproofing Reply: Hi. The insulation will not cause any issues.

21) Charles K: Thank you for providing a great educational resource. I can't seem to find a clear answer to my question anywhere. Do you advise against, or in favor of, filling the air gap in a double stud (decoupled) wall with insulation?

Trademark Soundproofing Reply: Thank you. We recommend filling with fiberglass insulation. You will still have the advantage of the air gap plus the absorption of the insulation.

22) Mike: We want to reduce sound transmission between our master bedroom and guest bedroom. (No high-volume audio equipment, but even normal conversation can be heard clearly.) We are quite willing to install a second wall to achieve a double stud wall. But how much space should we leave for the air gap? Will 2 inches be useful or not? 3 inches? 6 inches? And should we fill the air gap or at least the spaces between the joists with insulation? Thanks. Mike

Trademark Soundproofing Reply:

As long as they are not attached at any point even a half inch would suffice. You may want to remove the existing drywall before you start to avoid the triple leaf effect, fill the cavity with insulation and use double layer of drywall with Green Glue Damping in between on the new wall. (This will work if there is no open air space above the 2 walls).

23) Patrick: I am looking to minimize the impact of sound transferring from our kitchen to the basement rec room directly; impact related noise is the main item to be addressed as the kitchen has wide plank hardwood floors installed. The ceiling of the rec room has been partially removed as a result of water damage. The floor joists are engineered wood I-joists. The drywall is directly attached to the I-joints; glue is also present. There is fiberglass insulation (non-soundproof) installed between the joists. As a result of the water damage, there is a small area of the wood floor that has incremental squeaks. My initial plan was just to repair the damaged ceiling (approx 20% of the overall ceiling), replace the fiberglass installation with some soundproof installation, and hope for the best. After reading some of your information, I am evaluating whether to remove the entire ceiling, install channels for decoupling the drywall from the joists, and install new soundproof insulation between the joists. As this is a much more significant investment, I am trying to evaluate the cost benefit perspective. I would be interested in your thoughts and/or any changes to my proposed path forward. Thanks -

Trademark Soundproofing Reply:

It is incomparable. The 2nd way will give you real soundproofing vs the first way that will not do much more than what you had before the damage. Instead of "Hoping" for the best, "Do" the best Laughing

24) Jay: I am finishing a theater room in my basement. I have 2 exterior walls that are 2x6 wood with insulation and buildwrite and steel siding, the 2 interior walls are 2x4 and 2x6, room is 16' x 23'. Whatis your recommendation for finishing the walls? The ceiling unfortunately will be a suspended track ceiling, any advice on the panels and what to add above them?

Trademark Soundproofing Reply:

Hi Jay. Double layer of drywall with Green Glues for the interior walls. You can lay a ceiling sound barrier on top of the ceiling panels.

25) Ryan: If resilient channel is used how do you trim a window or a door without shorting out resilient channel?

Trademark Soundproofing Reply:

Hi Ryan. Great question. As long as the drywall is not attached to the door trim you will have no issues. You can attach the door jamb to the wall joists than butt up the drywall close to the jamb and fill the gap with acoustical caulk.

26) Gideon: Hello again! I had another question if that's okay: How much additional benefit do I get from decoupling both sides of the wall - so for instance how much better would case 1 be than case two in this example: Case 1: 2 layers 13mm gypsum with GG, isolation clips and resilient channel, 90mm timber with fibreglass insulation, isolation clips and resilient channel, 2 layers of 13mm gypsum with GG Case 2: 2 layers 13mm gypsum with GG, isolation clips and resilient channel, 90mm timber with fibreglass insulation, 2 layers of 13mm gypsum with GG Is it even worth having GG on both sides of the wall? Thanks!!

Trademark Soundproofing Reply:

Once one side is decoupled it is usually enough. Green Glue on the 2nd side is worth it.

27) Arnold M: As to value for money, which is best to reduce sound annoyance - better floor or better ceiling? No close neighbors so walls are no problem. Thanks; Arnold

Trademark Soundproofing Reply: If your question is: That you have a choice to do either the floor or ceiling. Than the floor may be a better option as footfall noise can be very annoying. On the other hand you can get better results usually when doing the ceiling as you can utilize the decoupling method. Therefore we advise you to treat both at one time :)

28) John Z: I have a school that wants to put classrooms below a gym space. The problem is when they are bouncing basketballs. What would the best solution be in that case. The structure for the floor above are concrete tees and concrete columns below. Thanks

Trademark Soundproofing Reply: Hi John. That is too broad of a question to answer here. Basically it would depend on if they are willing to frame another ceiling below the existing concrete floor and if not would they be willing to add to the floor above. You can call us to set up a consultation. 845-388-1200.

29) Melanie C: Hi! I just moved into a bottom-floor apartment of a very old multi-story building. The amount of foot noise I can hear from above (both from the tenants in their apartments and as they pound down the stairs) is tremendous. As I am just a renter, I am unable to modify the apartment beyond nailing materials into the wall (I can plaster and then repaint) and other removable alternatives. I also notice my room echoes a great deal, though I'd much prefer addressing the impact noise coming from (and around). Any tips on what modifications I can make or steps I can take to reduce the impact transmission?

Trademark Soundproofing Reply:

You can hang acoustical panels on your walls.

30) John w: I rent out a basement suite in a old house the floors are about 2in thick with sub floor Plank and several hard would finishes that have been installed over the years. The basement joistes are only 6 in deep. Part of the basement ceiling is drop ceiling. I removed the tiles and installed safe and sound it made a lot of difference with noise transfer in that area. The rest of the ceiling is dry wall. (Would blowing insulation in the drywalled part of the ceiling work as good as the safe and sound bats I installed in the other section) . Also would sandwiching insulation between 2 pieces of drywall work as good as GG between 2drywall sheets. joists are 24 in apart. Was hoping not to put too much more weight on them Thanks John

Trademark Soundproofing Reply: Cellulose blown in insulation should work just as well. Green Glue will work a lot better between drywall layers.

31) tim: For a drum room with low frequency issues, and limited space - would your recommend double 2 by 3 walls with DD/green glue O R clips/hat channel + green glue

Trademark Soundproofing Reply: if the 2 walls are completely separated without any bracing than the double drywall and GG is the way to go as long as you put some insulation in there.

32) Mike: Hi! First off, your website is awesome! I own a two unit and am attempting to reduce noise transmission from the upstairs tenant, to the downstairs tenant via the ceiling. Plan is to remove existing drywall, add Roxul sound barrier insulation 2? thick, decouple the ceiling via clips and rails, then construct the ceiling as 5/8 drywall, green glue, 5/8 drywall. Do you recommend anything else? should the perimeter of the first layer of drywall be acoustically sealed? Or just the last layer? Lastly joists are 2?x10?, should the entire 10 inch void of the joist be filled with the sound barrier insulation? Or is one 2? thick bat sufficient? Does doubling or tripling the thickness of the insulation make a difference?

Trademark Soundproofing Reply:

Thank you Mike! That is a great ceiling as long as you avoid recessed lighting cans that will cut holes through your layer of soundproofing. Rather use surface mounted lights that use standard electrical boxes that you can wrap with putty pads. Sealing either one of the layers with acoustical caulk is fine and we suggest you have at least 4-6 inches of insulation in your ceiling.

33) Susan: Thanks for responding. Do you have a product that I can put on the exterior of our house? All of our interior walls are finished and have built in shelving or cupboards. We were thinking of digging down the exterior of the house to the base of the foundation and wrapping the exterior foundation with something to absorb the sound or build a second wall on the exterior at the foundation level all the way up the exterior of the one side of our house.

Trademark Soundproofing Reply:

Take a look at our exterior soundproofing curtains.

34) Terry: Just getting started on a basement studio. 3 walls are poured concrete so that part is easy. On the 4th wall, I am planning 2 2x4 stud walls separated by 1/2 inch. Should/could there by drywall in the insides of these 2 walls? Also, I have over 1000 bricks leftover from construction. Any value in staking these inside one of these walls? Thanks

Trademark Soundproofing Reply: Do not put any drywall between the walls. Leave it as an open air space with only insulation in both walls. Soundproof the "outside of the walls, with layers of MLV and or drywall and Green Glue and make sure to seal your outlets and perimeters. Bricks will be a hassle and not that effective if you won't be sealing them at all joints. However you can stack that between the walls it won't be detrimental like the drywall would and will only help.

35) Christine B: My townhouse shares a common waster wall. A new owners moved in and the snoring is absolutely atrocious. Sounds like a buzz saw 12 hours every night. I got the plans and they are hard to read. It looks like there are 3-2x4s and then just an airspace. The airspace has an intermittent solid line showing on the plans inside the common wall. It says NOTHING about insulation and I don't believe there is any from the snoring. I wish I could send you a pic of the drawing of the wall. I am desperate. I don't know if I could insulate the inside of the wall due to fire codes and structure. What can I do to help insulate the common wall? I was thinking about putting another layer of drywall on top of the current drywall but don't want to cut into my master bedroom too much. Of course my bed is on the common wall which I just had that wall painted an accent color. I am dying with the noise each night. Please, please help. Thank you so much.

Trademark Soundproofing Reply: Sorry to hear that. If there is no insulation at all than you can blow cellulose insulation into the wall. Once the insulation is in you would still need better soundproofing like adding more drywall with damping compound. Additionally if there is a common airspace above the wall you would need to soundproof the ceiling as well.

36) Mark H: Hi, I have an installation question: I understand the practice of decoupled walls overlapping the ceiling of the room but what do I do with the decoupled walls in the four corners of the room - do we 'butt' the two decoupled drywall 'walls' and seal the right-angle with Green Glue Sealant, overlap one wall (as with the ceiling) or do you recommend another way of finishing the inside corners of a room where all four walls are decoupled? Thanks in advance, Mark H.

Trademark Soundproofing Reply: If the 4 walls are decouple from the exterior walls there is no issue with them being joined. If you are trying to decouple the interior walls from one another as well, than you would need to "join" the corners using a specialty resilient sound clip

37) Mo: Hi, I have a condo with a shared common wall. I don't know what's behind it, and I am not allowed to remove the drywall without going through the HOA (not worth the hassle). The sound situation is that I can occasionally hear low frequency sounds, like a door slamming. I can only hear voices if I hold my ear to the wall, and even then, the voices aren't real clear. I guess it's my long way of saying, the wall seems pretty well sound proofed already. That said, hearing the random banging sounds (sound like dull wood banging) is messing with my anxiety and I would like to reduce it if possible. How effective do you think it would be to add green glue, and then a layer of quietrock, over the existing dry wall? I read your article and am scared of making things worse. Unfortunately I am not really smart enough to understand what frequency I am trying to block, nor am I sure if adding GG + QR would create a triple leaf. Thanks. Mo.

Trademark Soundproofing Reply: You would not be creating a triple leaf and you may receive some benefit however if the banging is your main concern it will not be worth the expense as there is an impact vibration. Your better off trying to get something for those doors to close softly on.

38) Dr Mohammed H: I live in 1st floor of an 3 stored apartment. I am disturbed by dragging sound of chairs of top floor. There is a disturbing sound ,even a thing is dropped on their floor. They are listening to my complaint. What can I do to my ceiling, so that noise is minimised to a large extent. Thanks.

Trademark Soundproofing Reply:

You would have to remove your existing ceiling and start over as described in this article

39) Jim: Jim. I am trying to block the low frequency Bass from my neighbor's stereo. I have no problem with high frequency noise coming through my wall, just low frequency noise. There are a lot of conflicting answers about decoupling and low frequency noise. I've read that RC Channel has no effect on low frequency noise and can actually make it worse. I've read that an air gap between the existing wall and the drywall with green glue can also make low frequency noise worse. I've also read that mechanically attaching the drywall (with green glue) directly to the wall allows the bass to vibrate the added drywall reproducing the sound waves from outside to the inside of the home My question is: to block low frequency Bass noise "only" would it be better to attach 2 sheets of 5/8 inch drywall (with Green Glue in between them) directly to the existing wall. Or should I decouple the drywall with a one or two inch air gap. Also, if I added a third layer of drywall directly to the two layers of green glue/ drywall, would adding another layer of green glue in between those be counterproductive. Also, if adding a third sheet of drywall is productive, should it be a different thickness then the first 2 sheets. Thank you.

Trademark Soundproofing Reply: Hi Jim. Short answer for your situation would be. 1 layer of Mass Loaded Vinyl to existing drywall. Followed by Drywall, Green Glue and Drywall.

40) Srdjan S: Im soundproofing a ceiling with decoupouling clips,channels,drywall,green glue,drywall to reduce footfall noise from the upper unit. Now the ceiling has small sections where its dropped for ducting. Do i need to decouple the bottom amd sides of the dropped sections or can I just add another layer of drywall with green glue? Thanks

Trademark Soundproofing Reply: Those section should just be double drywalled with Green Glue no need to decouple them. If possible get some insulation in there as well. Keep in mind that if the soffits end on a wall (they do not go back up to the ceiling. Sound can get into the soffit and then travel down and out through the walls.

41) John M: Hello! I am in the process of sound proofing my garage and i have an over abundance of 1/4" thick x 4" wide rubber strips and a huge amount of cork in sheets. Would using the rubber or the cork as resilient channel work? Thanks for taking my question.

Trademark Soundproofing Reply: If you were able to attache your drywall to the rubber and cork only without penetrating to the joist it would help to certain extent, however not sure if that is a possibility.

42) Mike Jouk: Good day, Thank you for this informative article and answering the questions. I do not think I see my question answered yet, I apologize if I missed it. I am soundproofing my basement suite. I want to decouple ceilings from the floor above. I have the option of hanging fully decoupled ceiling via rim joist and joist hangers due to my current ceiling height. I was under the impression that this is the best option but now I am getting confused. Is this worse than hat-channels? Rim joist would be hung on existing studs. I thought this would be best for blocking footsteps? Thanks again!

Trademark Soundproofing Reply:

You are welcome. We would need more details as to this installation, however if your joist hangers are firmly attached to your joists and to your ceiling that would not be a decoupled ceilings and the resilient sound clips and hat channels would be a better option.