TM Soundproofing Soundproof Existing Walls & Ceilings

Soundproof Existing Walls & Ceilings

Topics Covered in this Article:

Read the article below if you find that you do not have the privacy or silence that you require in your you are in a condo, office building, hotel room or your own home.

For best soundproofing results you should consider removing your existing wall or ceiling and start the sound control process from your studs as detailed in our How to Soundproof article.

However if you prefer to keep your walls and ceilings in place and are content with a solid upgrade (about 6-9 STC points) then we have outlined the proper steps below.

(For more information on understanding how sound travels, see our Soundproofing Basics article).


For proper soundproofing you need to have some kind of absorption, usually that is accomplished by having insulation in your walls. To check if your wall or ceiling has any insulation in it, drill a quarter size hole in your wall and look in.

If there is no insulation you may want to consider pumping cellulose or loose fill fiberglass into your walls. You can usually rent the machine and DIY or have an insulation contractor do it. The process involves drilling holes in every bay and sticking a tube in and then pumping the bay full with either cellulose or fiberglass; there is no need to plug the holes as you will be covering the wall with another layer of drywall.

If there is even a little bit of insulation in the walls then do not bother blowing in the cellulose as it will get caught up in the old insulation and will not fill the wall properly.

Tip: Do not try to use any self expanding foams as these are expensive and not as effective as cheaper cellulose and fiberglass. In addition they will most of the time not fill your bays properly.


The next and most important step is to install another layer of drywall over your existing wall and ceiling. Our first choice is always to use 5/8 inch thick drywall, if that is not possible than 1/2 inch is fine.

Before installing, apply Green Glue Noiseproofing Compound onto the back of the new layer and then screw over the existing wall or ceiling as you would any standard drywall.

Applying Green Glue Soundproofing Compound to Drywall             Applying an Additional Layer of Drywall with Green Glue

How Much Do I Need? It is recommended to use 2 tubes of Green Glue on every 4 x 8 sheet. For more details see our Green Glue FAQ page, or Green Glue Installation Guide.

Now, depending on the noise type and noise level present, you may either finish your wall or ceiling at this point as described in the next paragraph, or you can proceed to install a additional layer of drywall with Green Glue over the 2nd layer (leaving you with 3 layers of drywall and 2 layers of Green Glue).

One of our suggestions here at Trademark Soundproofing is to have you install one layer of drywall with Green Glue and then wait about 10 days; if you are satisfied with the results go ahead and finish off the wall. If not then proceed to install the 2nd layer.

Soundwaves passing through ceilings

Important: When using this technique to soundproof a wall, keep in mind that if there is an open attic space above the 2 walls the sound will jump the wall and enter through the ceilings, see figure to the left. Even in places where there is no open attic space, sound can go over the walls through the air space above the wall that is created by the ceiling joists. This is especially true if the ceiling joists run over the wall from room to room.

The best solution for this is to install a 2nd layer of drywall with Green Glue on the ceiling in at least one of the rooms (preferably the same room that had the wall treated) in addition to treating the wall. This is a must if you have an open attic or crawl space.

Offices and Strip Malls: Usually have drop ceilings and the walls end at the drop ceiling with empty air space above the wall to the roof. This is a major cause of sound issues between spaces and treating the wall without treating the ceiling will not get the desired results. The proper way to soundproof these spaces is by building up the wall all the way to the roof line and treating the entire wall as mentioned above (Caulk all penetrations between spaces and top of the wall with Acoustical caulk).

If that is not possible building a drywall ceiling and treating it as mentioned above will work well.

When that is not an option either than you need to treat the ceiling with ceiling sound barrier tiles that are placed over each individual drop ceiling tile.


Applying Green Glue Soundproofing Compound to DrywallOnce you are done hanging your walls and/or ceilings, caulk the perimeter (the outer edge on all 4 sides) with a quality Acoustical Caulk. Be sure to fill the gaps fully, as a complete seal, with no air spaces.


STC Box Seal for Soundproofing Outlet BoxesYou can then spackle, tape and paint the wall as you would to finish a standard new wall. Seal all outlets in the wall with our specialty Outlet Seal.

The above described sound control technique has been used successfully by thousands of our clients, including hotels, office buildings and private home owners. You can do it yourself or hire a reputable drywall contractor in your area. There is no need for your contractor to have any prior experience in installing Green Glue. We will be happy to send you any materials you need and discuss any installation issues with you or your contractor.

[Keep in mind that this sound control technique is very good at controlling airborne sounds and some impact sound. However if your main concern is heavy footsteps or dragging of furniture then you will need to remove your ceiling and use one of our Resilient Sound Clips to create a floating ceiling system. Continue with installing insulation, hat channels, two layers of drywall with Green Glue as described in our How To Soundproof Article].

Click here to return to our Sound Control Homepage.

Copyright 2009 Trademark Soundproofing (Revised 2015). All rights reserved.


Customers Questions and Answers

1) Bill: I'm about to move into an attached house (row house). I'm not sure if sound proofing will work in this situation. There is a cinder block and brick common wall between the houses. The current sheetrock is on 1" furring strips attached to the sheetrock. I can sometimes hear music or conversation at a very low level coming through. I am not sure if it is coming up from the basement where there are some gaps in the wall that need fixing or over the ceiling. It sounds like through the wall. If I retrofit, then will the sound go away? Or is at so low a level now that it would be impossible to reduce it further? Is green glue, acoustical caulk and regular sheetrock enough or should I use Quiet Rock. thanks

Trademark Soundproofing Reply: Hi Bill, The GG is a very good performer on low frequency sounds, as in the ones that you are hearing. Being that you do not have insulation in the wall, performance is not at it's maximum. Standard sheetrock and GG will suffice. If you have an open air space above the wall than you would have to treat the ceiling too.

2) Sharon B: Will this green glue, one or two drywall treatment stop mumbled voices? That's what bothering us. Thanks for your help.

Trademark Soundproofing Reply: Hi Sharon, It would help for the sound that is coming through the wall (more so if you have insulation there, if not try pumping some cellulose there first).

3) Mark: What applying green glue and 5/8 drywall over a concrete wall. Will the green glue bond the drywall to the concrete wall without screws to hold it in place?

Trademark Soundproofing Reply:

No. The Green Glue is not a proper adhesive and should not be used as one. You would need to mechanically fasten the drywall to the concrete wall.

We also recommend that you use 2 layers of drywall on the concrete wall and apply the GG between them rather than between drywall and concrete. GG optimal performance is between layers of the same density.

4) Kevin : The noise from our upstairs has become more noticeable over the years. We have 2 bathrooms above our kitchen. Our kitchen ceiling has around 10 ceiling lights. What would be best method to dampen the noise? I am starting to think that the drywall is going to have to come down. Any ideas would be appreciated. Thanks.

Trademark Soundproofing Reply:

Hi Kevin, You are right about removing the ceiling. However it would only make sense if you plan on reducing the amount of recessed lights that you have there now. Consider switching to lights that can be surface mounted to the new ceiling.

5) David: I'm building a new house in which I need to provide room to room sound isolation between interior walls, to reduce television or recorded music sounds. My plan now is to use 2x6 walls with double 1/2 inch sheetrock on both sides and fiberglass batting inside. Using green glue between sheetrock layers and/or using blown in cellulose will cost more. How much benefit will I realize from them? Thanks, David

Trademark Soundproofing Reply:

Hi David, You will not realize that much benefit by using Cellulose over Fiberglass. However you will have a great benefit of adding the Green Glue about 9 STC points by adding it to one side and an additional 4 pints by adding it to the 2nd side.

6) JUDY : We have a finished dance studio and we need to sound proof it. We are adding more mirrors. Can we use green glue on the drywall and add mirrors over it?

Trademark Soundproofing Reply: Hi Judy, That would not help that much. You should consider adding another layer of drywall with Green Glue on the existing wall and hanging your mirrors on the new drywall (and we recommend doing the entire wall).

7) Debbie : In my retirement condo my neighbor with adjoining living room wall plays her music real loud. I have to turn my TV up almost double what I listen to then I still hear boom boom from the base. I hear her drop some items, of course nail pounding. The music is the most troubling for me. Is this expensive to hire out?

Trademark Soundproofing Reply:

Hi Debbie, If you have insulation in the wall adding a 2nd layer of drywall with Green Glue Damping Compound should drastically cut down on the low frequency sound of music.

8) Melissa: If we put green glue and then an extra layer of drywall over the existing drywall, how do we deal with any outlets/light switches boxes which would now be recessed by 5/8th of a an inch? Do we need to get an electrician to move the boxes forward or is there a less costly/easier fix? Also, what is the difference between using green glue and a sheet of drywall over the existing drywall, versus using a sheet of quiet rock over the existing drywall instead and what would you recommend for an upper floor ceiling, where there is access to the attic? Do we need to add a sheet of drywall on the ceiling, or can something be done in the attic to reduce the entrance of noise? Thanks for your help!

Trademark Soundproofing Reply: Hi Melissa, Usually the electric box can easily be moved forward, check with an electrician or search online. You can use QR, however according to some lab tests GG performs better. If the sound is from the room next door than either you have to build a wall in the attic between the rooms or treat the ceiling.

9) Lizabeth: I live in a town house and have a firewall and also blew in insulation and can her my neighbors all time. Running, jumping, music, voices and more. What is the best way to block out the noise from them? Thank you

Trademark Soundproofing Reply: Hi Lizabeth, Please read the article above. If you any specific question please ask it here. If would like to schedule a phone consultation (for a fee) please call our office to schedule.

10) Charlene: I needed to stop the footfall noise from upstairs that kept me awake at night. So, in my bedroom I attached 1 layer of drywall w/green glue between joists to bottom of subfloor, added insulation and MLV, Kinetics IsoMax resilient sound isolation clips, hat channel, and two layer of drywall with green glue between. I followed your installation directions, I nolonger hear the TV or voices, but now the sound of footfall from above is a deeper basslike sound that is more disturbing than before. its like im inside a subwoofer/bass drum when the neighbors upstairs walk. Why is that? How can I fix this so that I can sleep?

Trademark Soundproofing Reply:

Hi Charlene, That is a tough one. It may be caused by the MLV which is a thin layer and small space between that and the drywall. See our Triple Leaf Effect article. However I a cannot be sure about that without doing an actual site visit as you may have flanking sound issues down the walls or duct work. Thank You

11) David: I have loud neighbors who stomp literally all day and all night long and i never have a peace of mind. I installed fiberglass insulation above my bedroom and another layer of sheet rock. The noise is exactly the same. i understand that my condo was built very cheaply and not the right way. Is there anything I can do so i don't hear my neighbors? or is this just that way it is

Trademark Soundproofing Reply:

Hi David, You should apply a damping compound like Green Glue between the 2 layers as a minimum. If footstep sound is your main concern than you would have to remove the ceiling and decouple it using Resilient Sound Clips and Channel. However footfall sound is the hardest to eliminate and you cannot expect a full elimination of that (unless you start during the construction of the building).

12) David: Thank you for the response. Do you know any companies who use your products who can do sound proofing? Or someone who can come give me an estimate? Do you know of anyone who can replace ceilings?

Trademark Soundproofing Reply: Hi you can send us an email with your zip code. We have a database with contractors who are well versed with our products and consult with us. We will let you know if there is someone in your area that we can recommend.

13) Tom: What would be your suggestion to reduce noise between 2 bedrooms. Exterior walls & ceiling are all heavily insulated . Noise transfer between the two rooms is loud . Newer consrptruction wood studs, Sheetrock all smooth painted walls . Tiled floors, area rugs on a slab no basement. But every sound can be heard from master bedroom to bedroom next to it.

Trademark Soundproofing Reply:

Hi Tom. Are these 2 bedrooms under an attic or crawl space. If there is an open air space above the 2 rooms then you would have to soundproof the ceilings and the walls. Best way would be to add another layer of drywall with Green Glue in between,

14) Tom: Thank you for the response. Yes, there is an open attic over the bedrooms ( insulation is foam blown into joists) so the ideas suggested make perfect sense. Is there a simple way to deal with the attic ? Your suggestion on the green glue for the walls makes sense. Tom

Trademark Soundproofing Reply: We usually suggest adding another layer of drywall with Green Glue to the ceiling.

15) April: It seems your company favors the use of green glue. I have an existing wall to retrofit. What are the benefits over the use say of 1lb mass load vinyl sandwiched between sheet rock. Or could they be used in conjunction. Or is a third layer of 1/2 sheet rock preferable.

Trademark Soundproofing Reply: Hi April, That is correct as Green Glue will give you a better STC rating. If you want to use it in conjunction (which many of our customer do) you would need to add the MLV to the existing wall. Add a 2nd layer of drywall, add Green Glue and a 3rd layer of drywall. Thank You,

16) April L: I just reread the specs and noticed that green glue is not recommended for 16" center studs which is code here in San diego. Now I'm at a loss. Help

Trademark Soundproofing Reply: Hi April, Not sure where you saw that, please point it out to us. Most jobs using Green Glue are using 16 OC studs.

17) April L: I saw the data directly on the green glue site that testing was done with 24oc studs. A few other of your competitors sited this data also along with the warning that it is not recommended for 16"c studs.

Trademark Soundproofing Reply: Hi April, All sound manufacturers test their products on 24 OC studs as they get slightly better results than 16 OC (less connection points). Nevertheless in real world usage it is mostly used on 16 OC. The GG performs wonderful on 16 OC as all the reviews and our own installation can attest to that. I would be very curious to see a link showing a warning not to use on 16 OC as that does not make any sense. Thank You.

18) bob: we have a macaw and cockatoo and they scream up to 135 dbs they are in a 12x12 room finished. thought i would put insulation in interior walls, add a 2nd layer of 5/8 drywall with green glue. what else would you suggest

Trademark Soundproofing Reply: Hi Bob, You can add an additional layer of drywall with GG in between. So you would have 3 layers of drywall and 2 layers of GG. If you wanted to do something more extensive. You can remove the existing drywall. Add Insulation. Install Resilient sound clips and hat channel. On the channels install double drywall with GG.

19) Sara M: Hello! I'm researching how to do retrofit soundproofing for a residential renovation. It looks like MLV or Green Glue will be a big help. Is it effective to use them together? Or is that overkill and too expensive? I didn't see any tutorials about using them as an assembly, so I wasn't sure if it was advisable. I assume I would strip the wall to the studs, insulate as necessary, apply the MLV over the studs, then either apply a layer of gyp board with green glue or two layers of gyp with green glue in between. Thanks, Sara

Trademark Soundproofing Reply: Hi Sara. It is effective. The GG cannot be sandwiched with MLV so you would have to install the MLV first, then a layer of drywall, GG and a 2nd layer of drywall. If you are on a budget you can go with just the drywall and GG.

20) Sara M: Thank you! Do you have any charts or tables that quantify the benefit of adding the MLV to the gyp/GG sandwich? No big deal if not, I was just curious whether to advise clients to go the full monty (whether it's enough sound reduction for the extra money). -Sara

Trademark Soundproofing Reply: Hi Sara. We do not have a chart of the MLV with the GG. However testing on walls with MLV in there show a gain of 3-6 STC points. So you can assume a gain of about 3-4 points in a double drywall with GG system.

21) Jean P: In an existing shared wall which is concrete block structure (cbs), I hear both sound and closing of cabinet doors which are on the neighbor's side. The (cbs) goes all the way into the attic, but I also feel the noise carries over that space as well. My bedroom is next to neighbor's wall and hear all movement when the person closes cabinets, etc. Very frustrated as to what the best solution. Walls and Attic Space?? Please advise. Also can you recommend a contractor in Palm Beach County zip 33418?

Trademark Soundproofing Reply: Hi Jean. You need to soundproof the wall and ceiling as well if you have an open attic space above the 2 walls. You are best off with a stud wall and ceiling that has insulation and air space. Thank You.

22) Mary H: Hi ~ how many inches would this soundproofing detract from height of my home? Are there options here and what is the 'slimmest' option? I have new upstairs neighbors who are quiet noisy and I would like to soundproof my condo ceiling. Thank you Mary~

Trademark Soundproofing Reply:

Hi Mary. That would depend on which soundproofing method you wish to utilize. The thinnest possible is by using a 1 pound layer of Mass Loaded Vinyl which is 1/8" thick. That may not be practical as you would be left with a black vinyl on your walls/ceilings. Next and better would be to add a 2nd layer of half inch drywall with Green Glue in between. However if footstep noise is an issue you would really need to decouple your ceiling with Resilient Sound Clips about a 2 inch loss in space. Thank You.

23) Chris: Hi. I live in a rented apartment. I can hear my neighbor below snoring. My neighbor on the side is only connected by a 8x12 wall in the kitchen. I can not use most of the methods described. Adding drywall and such is not an option. I also have 2 metal doors. Sound comes through them greater than the walls. Do you have any suggestions for this type of situation?

Trademark Soundproofing Reply:

Hi Chris, You can try using a Soundproof Door Panel on your doors and Mass Loaded Vinyl for your Floors/Walls.

24) Gerhard S: Is it possible to get these materials in Canada? We live in British Columbia, on the west coast. Would you know a business here who does this kind of soundproofing? We hear heavy footsteps and squeaking of the floor above us and need to do something about it. Thank you.

Trademark Soundproofing Reply: Hi Gerhard Yes we ship to Canada on a constant basis please contact our sales department for details.

25) Zoe K: Hi, I live in a 1900 Victorian conversion flat on the ground floor. We can hear every step from our neighbours walking, banging, kids running and it's so load and vibrates. We are looking to find some options for us, either the whole flat or just the bedroom? What would your advise be?

Trademark Soundproofing Reply: Hi Zoe, If the noise is from upstairs you would need to redo your ceilings and crate a new ceiling using the decoupling method described in the article.

26) Anthony: I live near Toronto, Canada (Eastern Canada) and I was wondering if you have a Canadian distributor? I live in a townhouse with neighbours on both sides and this product seems to be a solution. I hear noises thru the walls from both of them. Thank you

Trademark Soundproofing Reply: Ahi Anthony, We do not have a distributor there at the time however we ship to Canada on a daily basis. Give us a call or email us and we will be glad to help!

27) Matt: I want to do a room within a room arrangement. The main room of the building has brick for the outer walls covered by plaster and lath. The ceiling is also covered in plaster. If I framed off half of the room to split it into two rooms, would I be able to leave a 1" air gap between the new framing and the plaster walls and avoid any triple leaf issues? Should I remove the plaster and lath and reframe, tear our the plaster above and decouple the ceiling? I can clearly hear footsteps above.

Trademark Soundproofing Reply: As long as you leave the the back of the framed wall (the side facing the exterior wall) exposed (i.e. not covered in drywall) you should not have any serious issue with the triple leaf effect.

28) Joe: I have a ceiling filled with Roxul insulation (2layers no air gap) & 5/8 FR drywall and still hear TV noise and talking. I do not want to take down drywall. Can I do resilient channel and another 5/8? or am I better off doing green glue and another 5/8 FR drywall? Thanks

Trademark Soundproofing Reply:

Hi Joe, you are better off doing a 2nd layer 5/8 drywall with Green Glue. We do not recommend a channel between 2 layers of drywall due to the triple leaf effect.

29) Sandra W: I live in the bottom floor of a stack condo. The neighbor above has a very heavy footfall. His dogs plays with hard toys for hours on end. They have hardwood floors. What can I do to help soundproof the ceiling from above? Any suggestion and who could do the work.

Trademark Soundproofing Reply:

Hi Sandra. Having your neighbor install carpet with our premium carpet underlayment would be your best choice.

30) liz: I own an exercise studio in a retail space of a shopping center. The tenet with whom I share a wall is unhappy with the audio bleed through that comes from our music. We've turned the music down and tweaked some of the bass from the tuner and it's still a problem. What recommendations do you have? And, might you have a referral for a company to come estimate the cost to soundproof? Thank you! Your website was so helpful. Liz

Trademark Soundproofing Reply:

Hi Liz. Thank you. If there is a drop ceiling on your space then it you would have to treat the ceiling with ceiling tile barriers. Additionally do your walls have any soundproofing? If not at least insulation and a 2nd layer of drywall with Green Glue would be the way to go.

31) sandy: How can I acoustically decouple a height speaker from the ceiling as my projector is attached to the same ceiling?

Trademark Soundproofing Reply:

Hi Sandy, You can use resilient sound clips like this one for that

32) Dennis F: I'm on the board of a condo association. We presently do not have any statement of required sound reduction for hard floor installation during remodels. The floor construction is a 4 inch lightweight concrete over 2inch subfloor of tongue and groove 6 inch plank which forms the ceiling in the unit below. We'd like to add language that requires the owner who are remodeling to provide adequate sound reduction. Do you have any suggestions for language that would be useful to provide direction on what would be reasonably attainable for remodels? Generally people are preferring to remodel with stone/ceramic tile products. Thanks, Dennis

Trademark Soundproofing Reply: Hi Dennis. Usually te terms STC is used. I.e. an STC of 50 and higher is required. For floors you would want to include impact ratings as well which is called IIC ratings. You would need to do some research to see what level you would want to require. One common issue with this is that we find contractors trying to reach a certai

33) Jay: Hello. Thank you for your tutorials so far, as well as your Q&A section, they have been very helpful. I own a townhome with one bedroom sharing a common firewall with my neighbor. It has fiberglass already blown into the drywall, and there is an open attic above which also has loose insulation blown into it. However, I have just installed tile into the bedroom (unfortunately had not thought about underlayments for the tile to reduce noise). Is there a non-invasive way to add some soundproofing to this room, in particular soundproofing that would allow it to become a piano room/music practice room? I am considering: adding a 1/2" or 1/4" drywall sheets on top of the common wall with green glue in between, as well as acoustic sealant for all the edges of the room, followed by foam padding on the walls. I am concerned that I might need to add more drywall/green glue to the ceilings? If I don't add to the ceilings will it derail my efforts to soundproof the wall, even though the attic does have insulation? Budget exists, but it is finite. Thank you for any insight you might have to offer.

Trademark Soundproofing Reply: Hi Jay, Thank you. Use the 1/2" drywall and GG on the wall and the ceiling. No point in doing all the work and not doing the ceiling, which is critical, at the same time.

34) Martha: Hi there: My apartment is in a 1940 heritage building in downtown Toronto. I have a shared wall that runs the entire length of my apartment. I can hear entire conversations from the neighbour as if they were in my own place. If the TV is on, even low, I cannot watch mine. I've taken off the baseboards and caulked all the way down [about 2 inches] into the space with Green Glue. I want to go the next step. As we are not allowed to drill/sink anything but picture hooks/nails into the walls, would I get noise relief with the green glue and one layer of Quietrock throughout, if I was able to nail the sheets on? Would that be enough [1 layer] to dampen the noise? The walls are solid plaster. Help. I'm going nuts.

Trademark Soundproofing Reply:

Hi Martha, Yes adding another layer of Drywall with Green Glue will help out tremendously. If you have an open attic above the wall then you would have top treat the ceiling the same as the wall.

35) steve: I own rentals, currently I have a 4 unit where the tenant have told me about hearing each other in there units. It's mainly in the master bedrooms there all back to back and stacked. Ok so I have an open first floor unit. I cut a hole in the wall and ceiling there is bats of fiberglass insulation in both wall and ceiling. so my plan is to put GG and 1/2 drywall on the wall and ceiling of the open lower unit hopping that will help. Then each time a unit opens do the same or at least the other ceiling on the other lower unit. and maybe the wall on the upper unit. I don't know. what do you think. thanks Steve

Trademark Soundproofing Reply: Hi Steve, That is a good direction to go and should benefit you a lot, keep in mind it can take up to 60 days for the GG to fully cure. One ting I would look out for is if you have any AC or Heat vents in the walls and/or ceilings that allow sound to travel through them.

36) Bryan: Great articles. We have a 5yr-old girl that is a light sleeper. Now we have a crying newborn. All 4 bedrooms are upstairs and it's all wood floors. My girl is in bedroom at the end of the hallway and on opposite side of hallway. Her walls are either outside walls or butt up against the other bedrooms. We put newborn in bedroom farthest from hers. Newborn's bedroom has the door and wall adjacent to hallway. Door to door is about 10ft. We have an attic with fiberglass insulation above. Both doors are hollow so I plan to put solid doors and door sweep, etc. I plan to blow insulation in the newborn's wall adjacent to hallway and add a layer of GG and drywall. We may also carpet newborn's room. Do I need to bother doing anything to the ceilings since the rooms are 10ft apart and opposite side of hallway? And do I need to bother doing anything else to my girl's room? Thanks in advance.

Trademark Soundproofing Reply: Hi Byran, I would add Gaskets and Automatic Door bottoms to the door(s). If you are adding drywall and GG to the wall in the room it is a good idea to add the same to the ceiling at that time as you will have to repaint the entire room regardless. Open attics above rooms carry sound no matter how much insulation and how far apart they are.

37) Zenon: Hi Folks, I'm looking to create a studio style apartment in the basement of my home. I've got three kids who love to run and play and (sometimes) cry. Aside from the floor joists, I'm pretty much starting from scratch. The home is a 1941 modular home, so it was prebuilt and bolted together on site. The floor joist system is a bit unique - double 2x8's span 4' OC while 2x4's run 16"oc and are perpendicular to the 2x8's. For the ceiling, I am thinking of doing the double 5/8" drywall with GG and sound clips/bar. For the joist cavity I'm a bit lost. Should I install fiberglass batt or Roxul batt? And where the 2x4 won't be touching the drywall, should I leave this as an air-gap or install batt insulation between the 2x4 and the drywall in addition to the cavity between the 2x4's? I'll also be replacing the sub-floor of the main floor above the basement and installing 3/4" TG plywood and hardwood floor cover. Can I do anything fantastic between the hardwood and subfloor to deaden the sound? Lastly, there will be some shared walls in the basement - they will be built using 2x6 conventional framing. Should I pack the cavity full of batt insulation (again which type is best)? For the wall cover, I was thinking of doing clips/bar, double 5/8" drywall and GG on both sides. Will this be effective? Anything else you might recommend? Thanks! Zenon

Trademark Soundproofing Reply:

Hi Zenon, Fiberglass or Roxul will both be fine. You should try to get a minimum of 5" of insulation in the ceiling cavity. You can either add a 2nd layer of plywood with Green Glue in between on the subfloor if you will be nailing your hardwood down. If you will be using a click floating hardwood floor system you can first apply a layer of rubber underlayment.

38) Carol F: I recently moved into an older condo (1973) in Toronto, Canada. For the most part, the apartments are fairly soundproof, especially side to side. e.g. my neighbour across the hall plays his music quite loudly and I hear it in the hallway, but only at my front door. However, up/down noises seem to carry and I have a budding clarinetist above me. In the summer I have a heavy hum in my apartment from the ductless A/C unit from the same apt above me. Our building has electrical heat in the ceilings which would be concrete. Guidelines for renovation are pretty strict. One cannot install light fixtures or do anything in the ceiing without doing a scan to see where the heating wires are. The wires start 6" from the edge of the wall. As I read all the comments here it doesn't seem to me that using green glue or soundproof drywall would work. Firstly because of the difficulty installing it, which might be able to be overcome. But mainly because I think some of the sound travel is vibrational, through building vents, etc. Could you please comment and give me your opinion of the value of using green glue/drywall on the ceilings of the apartment only. thank you carol

Trademark Soundproofing Reply: Hi Carol, You will have some relief however probably not enough for it to be worth your hassle. That Hum is a vibration and you would need some sort of decoupling. As is usually the case it is extremely difficult to pinpoint sound travel on existing structures. It is so much more simple and cost efficient when it is done in the pre construction planning. At that time we can also help plan the duct and pipe layout which is the cause of so many sound issues. It is unfortunate that so many builders are not properly informed in the correct way to sound control projects and it is a very frustrating point for us over here as we receive so many post construction complaints when the builders refused to deal with the soundproofing properly during construction.

39) Brittany C: Hi, I have several conference rooms I'd like to be soundproof without doing major remodeling work. Any ideas or recommendations?

Trademark Soundproofing Reply:

Hi Brittany, If the conference rooms have drop ceilings than you mitigate the sound problems by using ceiling tiles etc without having to do remodeling work as shown in this video. Keep in mind that for really proper soundproofing walls and doors need to be done as well. Walls will require the most remodeling. Doors, not that much.

40) Carl : Hi, I'm adding a (10' x 11' - 8' height) drum room in the basement of our home. Our walls are 2x4 wood stud; wall make-up: Roxul AFB insulation, resilient channel, 2 layers of 5/8" with GG between, acoustical sealant around the edges of drywall. The ceiling, to me, is much trickier. 18" tall truss-style joists, do I do my best to fill them completely with the same batt insulation or put nets between the joists and fill the area with blown in insulation? It seems easier to blow it in, just curious if it'll give the same sound insulation? (after the insulation the ceiling will receive the same treatment as the walls)

Trademark Soundproofing Reply: Hi Carl. Once you get 6 inches or more of insulation in there you should be OK, adding more will only give you minimal benefit. Your doing a good job on the walls and ceiling.

41) Suma: Is there any solution to soundproofing a house which is 1/2 mile from interstate highway ? Highway traffic noise becomes unbearable in the night without a white noise machine. Do you suggest any wall or window sound proofing? Any contractor can come and assess the problem? Thank you

Trademark Soundproofing Reply:

Hi Suma. There are solutions for everything, however on existing rooms it can take a lot of work that many people are not ready to do. I wuld suggest that you start with a window soundproof panel on your windows. If that helps and you still feel that you need to do more you would have to then treat your walls and ceilings as described in the article above.

42) Jeremy T: I have a 2-story home of which I am gutting the entire first floor (750ft2) down to the studs. There are bedrooms directly above so we want to create the downstairs a place where we could entertain and watch movies in "theater mode" (loud with bass). I do not plan to add ceiling speakers, but there will be in-wall rear speakers, and ceiling recessed lighting. There are also 2 cold air return to deal with within the ceiling. My plan was to add R-19 of insulation (faced or w/o facing?) to the ceiling while using "airtight" recessed cans for LED lighting. For the cold air return, maybe there's some sort of a baffle to reflect sound from the duct, but I have no knowledge of this. The ceiling will be hung in a single layer using hat channel 24" OC with clips 4' apart. My ceiling is only 91" high. Any suggestions would be fantastic as I am paralyzed on what to do or if its the right way. There's too much to read and too many conflicting suggestions. Budget is of consideration. Many advanced "Thank You's"!!!

Trademark Soundproofing Reply:

Hi Jeremy, If you are using LED lights there are surface mounted ones that you only need to have a small hole for a wire to poke through rather than a large cut out in the ceiling (we'll be posting a video of this shortly on our You Tube channel). R-19 Insulation, clips and channels is a very good idea. You should consider 2 layers of drywall with Green Glue damping compound in between. This is really good for low frequency sound such as you have in a theater. Not much you can do on a budget with the open air return however I would suggest that you cover the back of that and the speakers with mass loaded vinyl, similar to what we did in this video

43) Alex S: Green Glue didn't help much, what next? Here's what I've done so far: The wall I treated is about 8'2 x 17'. The floor and ceiling of my room are steel and cement with a solid 12 inch steel and cement column on either side of the wall. The shared wall between me and my neighbor is approximately 5 - 5 1/2 inches thick made of solid plaster/cement with some channels for wiring. I used roughly 2 and 1/2 tubes of Green Glue per 4x8 sheet and Green Glue Sealant in between sheets and also at the top and bottom of each sheet to fill the 1/8th recommended gap. I can still hear my neighbors voices. What would you recommend I do next? -Alex

Trademark Soundproofing Reply: Hi Alex, I am sorry to hear that. Surprisingly concrete is not that good of a sound blocker. I would have recommended that you first frame a wall of the concrete wall in order to create an air space and allow you to install fiberglass batt insulation. Green Glue application without an air space and absorption behind it does not perform well. Another thing I would check on is if you have an open air space above the wall (attic or crawl space etc). In that case you must soundproof your ceiling as well. Once you take care of your ceiling you can proceed to treat your wall as described above. Hope this helps. Thank you.

44) olive: My bedroom is about the living room in my apartment and I can hear talking etc. when I go to bed. Can I blow insulation between the apartment living room ceiling and my bedroom floor. Thank you.

Trademark Soundproofing Reply: You most definetly can. It will somewhat however you may still require some more. It is a good first step.

45) Mark: Hello, we live in a semi-detached house with a concrete separating wall in the basemenept, which is very quiet, but cinder block on the main and second floors, which allows all manner of noise. Can we put green glue on the cinder block and put drywall overtop, or do you recommend another solution?

Trademark Soundproofing Reply:

Hi Mark. You can however without an airspace and insulation behind the drywall the results will not be that great. You are better off framing a wall filling with fiberglass insulation and covering with 2 layers drywall and Green Glue in between.

46) Martha: I live in a condo on the bottom floor. I can hear the people upstairs walking, vacuuming and moving furniture. Can installation be blown in my ceiling to make it sound proof..

Trademark Soundproofing Reply: It would be a good first step and help somewhat. For proper soundproofing you would need to do more as described in the article above.

47) Danielle: Hello, I am in the beginning phase of escrow on a 2-story home. I plan on turning the downstairs into a rentable in-law. I still have time to back out of escrow, and am seeking expert advise on soundproofing. The floors upstairs are beautiful engineered wood flooring and some tile. I would hate to have to carpet them beyond area rugs, as the home will lose it's ambience and character. Right now, the impact sound is carrying downwards considerably. This is a big purchase, and I will be relying on the income from a tenant downstairs in part for home costs. I have been speaking with a drywall contractor who is knowledgeable about soundproofing. He is recommending removal of the existing drywall, Roxul, and then decoupling with RSIC clips & Hat Channel, and using Quiet Rock to finish off the soundproofing project. I am wondering if there will still be considerable impact sound transmitting downward from walking in the home after the work is complete? The kitchen will sit above the apartment bedroom, and I'm of course concerned about clanking pots and pans type noises transmitting downward, as well. I do not wear shoes in the house, and do not have pets or children. There are also 2 separate HVAC systems, but I'm assuming there are ducts in between floors for the upstairs area. In your professional expertise, do you think that the contractor proposal may mitigate impact sound enough to turn the downstairs into a viable rental. Thanks so much.

Trademark Soundproofing Reply:

Hi Danielle, If the downstairs ceiling is flat all across with no soffits and drops (that house HVAC etc) and does not have a large amount of recessed lights, then yes. Your contractors suggestion is a very good one and in our experience would provide sufficient privacy to allow for a rental (It won't be perfect however privacy is usually achieved). The only thing I would change is to use 2 layers of drywall on the channels as that would add weight on the channels and the ceiling and allow you to overlap the seams. You can use 2 layers of standard drywall with the Green Glue Damping Compound in between for best results. Make sure to caulk the perimeter with acoustic caulk and use surface mounted lights.

48) Danielle: Terrific! Thanks for all your information! Could you clarify what you mean as "drops (that house HVAC etc)?" Do you mean ducts that are used both for the upper and lower floors, with heating vents going to the downstairs ceiling?. In this case, there are probably HVAC ducts between floor but only for the upper floor and not shared with the lower floor, which is on it's own separate heating system and HVAC vents on the floor, not the ceiling in the lower unit. . I will now look at your products for ordering.

Trademark Soundproofing Reply: Sometimes ductwork is run underneath the ceiling joists and framed underneath creating a soffit which is a lower ceiling than the rest of the ceiling. Thanks, if you need help choosing your products just give us a call we are happy to help!

49) Dan C: Hello, I am in a first floor condo. I ]want to mitigate noise from the condo above me. Foot noise is he main problem along with some talking, (when loud). i have removed the existing ceiling down to the joists. The joists are open trusses style. I am in the process of attaching two layers of 5/8": drywall to the underside of the sub-floor above with layers of green glue in between. What type of insulation would you recommend for in the joists? I am also going to decouple the new ceiling with clips and hat channels with two layers of green glue in between. Am I on the correct path? Any other suggestions? Thanks,

Trademark Soundproofing Reply: Standard fiberglass that fills the entire cavity will suffice. You are on the correct path and doing a very good ceiling you should see (or rather hear :)) a big difference in the sound reduction once you are done

50) Carol: I have a therapy clinic with too much sound transfer between 3 treatment rooms. Had sound transfer previously between office and treatment room, and adding wall between top of demising wall to subceiling resolved the issue. Interior walls constructed with steel studs and no insulation between walls. Lease the space so do not want to do any more construction that I have too. Am not looking for total sound proofing but reducing sound transfer. Also need to keep odors and chemical use down due to children's sensitivity. Would you have any recommendations? Thanks very much!

Trademark Soundproofing Reply:

Hi Carol. You probably have the same issue on the interior walls as well, with sound going over the top of the walls. You can remedy that the same way you did between office and rooms or you can use our ceiling tile barrier as shown in this video

For the walls itself you need to at least blow cellulose insulation into the empty cavities and then cover with a new layer of drywall with Green Glue if still necessary (the insulation alone may be enough for your situation). For odors etc I would highly recommend that you use automatic door bottoms and gaskets for your doors too.

51) LYNDA L: We live in a downstairs condo. Outside the bedroom window is 4 heatpump units that are very noisy. We have installed new windows and I believe there is insulation in the wall. How could we eliminate the noise we hear from the heatpumps?

Trademark Soundproofing Reply:

You can put sound control curtains around the pumps or try a soundproof window panel for your windows.

52) terry k: Terry: I am creating an in law apartment in the basement of my home. I want to sound proof it as best as possible. I have 2x4x14" wood trusses supporting the living room floor above the basement. I've filled the spaces inside of each truss with 8 pound density Roxul mineral wool insulation as well as installation of 8" of Roxul between the Trusses. I have constructed a ceiling support that is completely disconnected and therefore independent of the floor up above. Then, in between the independent ceiling beams and the floor trusses I am thinking of installing 5.5 inches of denium insulation for the different sound frequencies and then I was thinking of using the green joint tape between the ceiling beams and the first layer of 5/8 drywall. Then I intend on using Green Glue between the 1st and 2nd layer of 5/8 drywall and also using the green joint tape on all tapered joints on top of the first layer joints. I intend to do the wall construction in a similar design, with complete disconnect and independent of and walls or floor construction from above. My question is " Would you recommend a third layer of 5/8" drywall on the ceiling and perhaps the walls with Green Glue in between them or not?" cost is not an issue. Sound transmission is. Please advise. Thanks, Terry

Trademark Soundproofing Reply:

Hi Terry, Your ceiling is very good. Once you do the 2 layers of drywall and GG to your fully decoupled ceiling the next best thing to do would be the floor above. If you cannot work with the floor above than I would suggest that you wait a few days after finishing your 2nd layer, do not spackle or tape and listen to the sound from above. If you are satisfied go ahead and finish the ceiling, if you feel that you still want some more you can then add the 3rd layer of drywall. It is a good idea to finish the walls with double layer and Green Glue as many times you have pipes and flanking sound coming up and down the walls. Try not to use any recessed lights in the ceiling rather surface mounted lights.

We wish all our customers would say "Cost is not an issue, sound transmission is" Smile

53) Henrich: Hi, my girlfriend owns a condo and is very annoyed by footsteps from upstairs neighbor with squeaky floor. I believe the building was cheaply built with no sound insulation at all, and floors are old and squeaky. I am wondering if convincing her neighbor to change his floor is more efficient than tackling the problem from below? If so, what is the best soundproofing strategy for his new floor in term of type of wood and subfloor reinforcement?

Trademark Soundproofing Reply:

The right way to help with the floor squeaking would be to remove the entire subfloor. Fill the joists with insulation. Put down the joist gasket tape onto the top of the joists. Lay down first layer of plywood, apply green glue damping compound and then lay down second layer of plywood. If that is too much work see if they are willing to put down carpet and use our premium carpet underlayment as padding.

54) Henrich: Thank you for your answer. would an island floor on top of the existing one help? what is the cost estimate for an island floor for a 600sqf approximately?

Trademark Soundproofing Reply: Sorry I do not know what an "island floor" is.

55) Jon: I want to soundproof a wall for a Hone Theater. How does Mass Loaded Vinyl compare to this method and can the two methods be combined?

Trademark Soundproofing Reply: They can be combined if you first install the Mass Loaded Vinyl and then 2 layers of drywall with Green Glue in between over the MLV. If you had a choice of either one the layer of drywall with Green Glue will give you better protection as it incorporates additional mass plus damping.

56) Ted: I'm advising a friend who has noisy neighbors above her condo. She hears heavy footsteps, doors closing, and objects dropped on the floor. The floor above is bamboo over a wood subfloor. Without removing the 1/2 inch drywall ceiling, options are 1) drill holes and blow cellulose into 2x10 joist cavities, and/or 2) add GG and a second layer of 5/8 drywall, or GG plus a layer of 5/8 QuietRock, possibly followed by 3) a third layer of GG plus 5/8 drywall or QR. I understand there are diminishing returns when combining treatments. Can you quantify in terms of STC points the benefits of the flowing assemblies, with and without blowing in cellulose? GG + 5/8 drywall GG + 5/8 drywall + GG + 5/8 drywall GG + 5/8 QR GG + 5/8 QR + GG + 5/8 drywall Also, I've read that GG is very good at reducing low frequency noise, but also that the only way to address the low frequency impact noise is to remove the ceiling and decouple with clips and channel. Which is it? Would really like to avoid removing the ceiling, but don't want to waste our time and money if doing less won't work.

Trademark Soundproofing Reply: She is mostly hearing impact noises. The STC rating will not help for that. You need to decouple the ceiling first.

57) Ted C: Thanks. She's also hearing people's conversations, so it's not all impact noise. It would still be helpful to have an answer to my question about the STC reduction of various assemblies. I know GG adds a few point, QuietRock adds a few points, but I'm not sure how much it helps to start adding multiple layers. If anyone has actually quantified that, I would like to know the results. thanks, Ted

Trademark Soundproofing Reply: We don't have testing to be able to quantify that. The general rule is that you usually receive half the benefit with each layer. I.e. 2 layers drywall with GG 9 STC points reduction. 3rd layer of drywall with GG an additional 4 points.

58) Lance: Just bought an older Townhouse Condo and sadly sandwiched in between two very noisy neighbors. Will use the hat channel, two layers of sheetrock and green glue for the bedroom, however the kitchen presents a unique problem. After we do any kind of sound proofing we'll have to hang cabinets on it. Any advice ? Thank you

Trademark Soundproofing Reply:

We have a special resilient sound clips for applications that require the hanging of heavy material see here

59) Ed T: Can you tell me is the Green glue is strong enough to be used in the ceiling without attaching it with screws?

Trademark Soundproofing Reply: It is not. Green Glue should not be used as an adhesive.

60) Tom T: Can the hat channels with clips be used on existing walls that have sheetrock? Thank you

Trademark Soundproofing Reply:

It can. However certain frequencies can be amplified due to the triple leaf effect therefore we recommend that you remove the existing drywall and install your clips directly to the studs.