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buyorsell888

soundproofing?

buyorsell888
14 years ago

Our only bath is between both bedrooms. Heads of the beds are against bathroom wall because of windows/doors etc.

There is a short hall to the living room/dining room.

For fifteen years I have lived with every noise in the bathroom being heard throughout the house.

Now that it is gutted, I want soundproofing!

all we find at Home Depot is a fiberous board stuff that DH will have to cut down to fit between the studs and of course, insulation but nothing else for soundproofing. Is there anything else?

Comments (23)

  • zinnah
    14 years ago
    last modified: 9 years ago

    There are many good reasons to soundproof a bath. Here are some of the things I do. Mass is important so use 5/8 rock, 2 layers if possible. Isolate the drywall from the framing by using metal RC channel installed horizontally across the studs, probably must go to a drywall supplier to find this channel. Make sure no screws go through drywall into the framing. This step is probably the single most important upgrade you can do. I go one step further and install channel on dense weather stripping to further isolate the channel. You can install that fiber soundboard under the drywall, though I prefer the RC channel, it is faster too. Installing fiberglass insulation in the stud cavities helps to absorb sound. Put expanding foam around electrical boxes so sound is not transmitted through them. A lot of sound can be transmitted through heating ducts, though I do not know of effective ways to isolate them. Make sure door is solid core and fits well especially at the bottom, the door can also be weather stripped as the foam helps absorb and isolate sound transmission. Hope this helps and helps to reduce those pesky sounds. Making a home sound resistant is something that is too often ignored.

  • buyorsell888
    Original Author
    14 years ago
    last modified: 9 years ago

    DH does HVAC for a living but there won't be a heating duct in the bathroom. There has not been a working duct in there for years, he blocked it off because it was transmitting sound. Using radiant floor heating, we did have a heat lamp.

    He gets up at 4:30 every day and I've never needed to get up earlier than 8:00 and am not. a. morning. person. so any soundproofing will be appreciated. I don't know why builders don't do it. Cost I guess.

    Bath only 5' w x 9' l and keeping existing tub so most likely cannot use two sheets of drywall. Will use fiberglass in the cavities for sure.

    We do need a new door too. Good point on solid core.

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  • reyesuela
    14 years ago
    last modified: 9 years ago

    Green Glue is the cheapest and most effective solution. It works great. It's visoelastic dampening rather than relying on mass. Check out the STC ratings. They ship and are easy to deal with.

  • MongoCT
    14 years ago
    last modified: 9 years ago

    Besides what's already been mentioned, look into Roxul insulation instead of fiberglass.

    Also look at mass loaded vinyl. Expensive, but you'd just need enough for one wall.

  • johnfrwhipple
    14 years ago
    last modified: 9 years ago

    There is many ways to reduce sound transmission and cut down on noise in the bathroom. Many of the tips above are used everyday with little or no success and this is because the plumbing in a perfect world would not be on a shared wall. The best and surest way to cut sound down is to alter the framing of the wall from a standard partition wall to a "party wall" type construction.

    A party wall can be built on a 2"x6" bottom plate and the studs are alternated so that the noise can't transfer between the studs. Here in Vancouver all apartment buildings are built this way (Party walls we've seen are build like this - Drywall, stud, insulation, off set, insulation, stud, Fireboard, Drywall (notice there is three sheets of drywall)). Now this will help a bit but to further reduce sound look into "Quiet Rock".

    Quiet Rock has been on the market for years and we have used it on 5 jobs to date with outstanding results. Quiet Rock also sells a chaulking and sound proofing sheets for wrapping your electrical boxes.

    Using 5/8 fireboard on the bathroom walls and covering them with Kerdi will give you a waterproof dense wall but not attaching the drywall to the studs is risky in my opinion.

    If should rebuild the entire wall between the bathroom and the bedroom. No need to take anything down. Just have your framer add a 2" strip of wood along this wall. Use Roxul's Safe and Sound insulation between your normal studs and install Quiet Rock to your existing Bedroom wall end to end. Dont forget to install Safe and Sound insulation in the floor joist cavity as well.

    You will notice a huge difference with these steps. Quiet Rock is the equivalent of installing 17 sheets of dry wall. This product is expensive my last order was $145.00 per sheet for their premium product. They make a grade 'B' product that is very good and sells for about $85.00 per sheet. In for a penny - in for a pound - get the good stuff and do it right.

    We have used it to block out street noise, kid noise, highway noise and of late a new renter in an apartment building that likes "Jam of the Electric Guitar" at 10:00 PM.

    Hope this helps,

    Good Luck.

    John Whipple

    "When it's perfect. It's good enough."

    More Reading and Resource Info;

    https://www03.cmhc-schl.gc.ca/catalog/productDetail.cfm?csid=1&cat=18&itm=11〈=en&fr=1268749131853

    http://seattletimes.nwsource.com/html/realestate/2003725962_homeforum27.html?syndication=rss

    http://books.google.ca/books?id=bAzKQEJMs58C&pg=PA249&lpg=PA249&dq=party+wall+construction&source=bl&ots=7B-L9mdXjl&sig=MiDqPbCVkbQJG3wvxMpu4x9oDSY&hl=en&ei=lJOfS-q0BZGgsgO1kMG1Cw&sa=X&oi=book_result&ct=result&resnum=6&ved=0CB4Q6AEwBQ#v=onepage&q=party%20wall%20construction&f=false

    Here is a link that might be useful: Quiet Rock

  • reyesuela
    14 years ago
    last modified: 9 years ago

    > Quiet Rock is the equivalent of installing 17 sheets of dry wall.

    Quiet Rock is a scam. All it is is thin sheets of drywall with an inferior visoelestic dampening material laminated between them--charging you roughly 3xs as much as using Green Glue. If you knew anything about soundproofing, you'd know what it is.

    If you knew anything about sound insulation, you'd also know that it's not STC but IIC that is the significant contributor to noise between floors, and in-joist insulation does almost nothing for that. Adding mass to the floor above and isolating the subfloor from the joists are two good strategies for bathroom floors. Resilient flooring is always better than tile for sound mitigation, BUT most people want tile in the bathroom no matter what. You can also use resilient channels in the ceiling of the floor below to minimize sound. Sure, insulation in the floor would be a nice addition....BUT its contribution would be pretty minimal compared to ANY of the other measure I've already mentioned. Galvanized iron drains (for the waste part of the waste-vent stack) are quieter than PVC, but I chose PVC because it's just a one-story drop (more important if 3 or more stories) and because it won't rust eventually and leak.

    Mass-loaded vinyl is way more expensive than Green Glue and way less effective, and in-the-wall insulation is fairly cheap but not particularly effective. Most people who want the maximum STC rating with the minimum cost and the minimum amount of thickness to the wall choose Green Glue between two layers of drywall with insulation int he cavity, but realize that the insulation contributes to maybe 10% of the total STC rating. It's just so cheap that it's hard to NOT do. If you REALLY want a quiet wall and can give up another 1/2 inch, you can add resilient channels to the studs on one side, and if you can give up even more space, you can do an 8" thick double wall with staggered studs, MLV or insulation, resilient channels, and Green Glue between two layers of drywall...but that'd be some crazy overkill.

    Green Glue is better than Quiet Solution's knock off, but both Quiet Solutions and Green Glue are FAR cheaper and more effective than ANY other option, and they only require a 1/2" extra of space on each side of the wall.

  • davidro1
    14 years ago
    last modified: 9 years ago

    The posts above are all trying to get to the following result:

    Both solid mass and light airy stuff, in layers, and totally airtight at that.
    Any hole means sound will come through.
    Isolating and dampening between layers is good too.
    The product you use could be almost any product, for each of these steps.
    Post again when you find products you might want to use.
    Sometimes it's deceptive, and you would be best off not using a product.
    Like many, I can comment about some of the products but not all.

    The first response was all good, except not the fiberglas.
    The next response, about dampening, was good.

    Fiberglass doesn't stop much air or sound compared to far better products like Roxul or cellulose. Isolating your drywall from studs is good, and not that big a deal in a small room like a bathroom. The drywall is still held in place very well, with channels. It's the same principle as furring strips. If you don't have the room for this extra thickness, it's ok, as you'll still have made tons of improvement by building airtight layers that are dampened. If you cannot double thickness with your current studs, use thinner studs. Any panel that is dense is good. I've used CBU. Airtight is a key word, and foam is good for this.

  • johnfrwhipple
    14 years ago
    last modified: 9 years ago

    For the record as it appears from Reyesuela post that "If you knew anything about soundproofing, you'd know what it is." is referring to me not knowing about sound proofing or is referring to me not using Green Glue.

    Seven years ago when I was asked to help reduce sound in a basement suite and especially the room between the kids playroom and the suites living room I researched the subject to death. The findings let me to similar post mentioned. We had good success with this wall but I knew we good do better.

    15 years ago when I was living in a condo and my living room wall shared my neighbors bedroom wall this was a touchy subject and I lived through many versions of sound proofing attempts to make him happy. In the end he sold and moved away - me too.

    My last 5 jobs have been easy. My clients have bucked up and installed Quiet Rock - every one of 5 has noticed a huge difference. They all rave about the difference and 2 of 5 sent me away with wine at the end of the job. Not sure how scientific that is but if 5 out of 5 love it and 2 of those 5 or so happy them make a point of writing a thank you card and buying their contractor wine I would have to think that this is a really happy client.

    Now I'm not a professional sound proofer - I build bathrooms and fireplaces mostly. I'm not sure I have ever read that CBU or backer board can be mounted to the sound reduction channels and I'm not sure if there is any added deflection - I do know that our CBU is installed rock tight to our framing members and I do know that deflection equals cracks and failing tile.

    Many clients who spend no money on sound proofing notice a huge difference just from insulating their water lines and pipes with foam pipe wrap and I believe that Kerdi helps with sound reduction as well - as clients have commented on how quiet their new shower is when I did nothing other than remove drywall and replace with CBU and Kerdi.

    Last night I meet again with my new client about a luxury build we have coming up and the subject of sound proofing was brought up by them. This is not your everyday reno. We will be installing over $20,000 of Dornbracht fixtures in this tub to steam shower conversion.

    Leave it to the German designers to design the packaging material for their beautiful products to help in sound reduction. The packaging that cares for these pieces gets reinstalled around the rough in's and is spec'ed in their install book. Since we are running new 3/4" supply lines their will be a lot of water flowing through these fixtures and the styrofoam wrap should help to reduce the noise.

    Adding layers, mass, green glue, quiet rock as mentioned by us all will improve your current system. Altering a walls thickness can create other problems with door jambs, window sills and such and should be carefully calculated. If you save $300 using green glue over Quiet Rock but have to use two sheets of 1/4" drywall the wall will be wavy. If you fir this wall out your door jambs and window jambs will need to be redesigned.

    One more point - from time to time it's written about people finding out that their water pressure is too high and there is no PRV - Pressure Reducing Valve in the home. Often adding this can help as well with plumbing noise as water travelling through 90 degree elbows and fixtures is less noisy at 70 PSI than it is at 100 PSI (Pounds per Square Inch).

    But what do I know...

  • dedtired
    14 years ago
    last modified: 9 years ago

    Would any of the above apply when the sound is coming from overhead? My upstairs full bath is right over the kitchen. Hope this is not TMI, but when someone up there takes a leak, everyone in the kitchen has the urge to put up an umbrella. I swear the sound is somehow magnified. So when I have the bathroom renovated, is there any way to muffle the sound between floors?

  • davidro1
    14 years ago
    last modified: 9 years ago

    Yes, it's TMI but it's OK.

    Start a thread "soundproofing between floors". This thread is about walls.
    Include information about your subfloor. Take your time to get some facts together first,
    if you want answers instead of being peppered with a thousand questions.

  • reyesuela
    14 years ago
    last modified: 9 years ago

    >If you knew anything about soundproofing, you'd know what it is." is referring to me not knowing about sound proofing or is referring to me not using Green Glue.

    About soundproofing. You answer lots of construction questions with general knowledge, not well-researched answers that stay CURRENT with the times. You don't know that Quiet Rock is thin layers of drywall laminated with Quiet Solution's Green Glue knock off and upcharged hugely. I don't think you know what STC rating should be a reasonable target--or what IIC rating, either--or how to get it or what kinds of noise are STC and which are IIC.

    You're recommending a product that, with labor, is at least twice as expensive as Green Glue sandwiched--and without labor, is 4x as expensive, at least--and does not perform as well on the basis that you've used it before and people like it. Well, they may like it, but it's overpriced for anything except jobs in which time is more critical than any other factor or labor is outrageously expensive.

    It'd be like me saying, "Well, I've used fiber cement board for 15 years, and it works great," without acknowledging the superiority of Kerdi for certain applications, without taking about its moisture-wicking properties, and without talking about the workability of cement board versus fiberboard and without saying that you shouldn't use it on a slab or that Ditra is better for some things or that a SLU is needed in some instances and is a dandy underlayment when you use it.

    I'm not a professional in the area of sound abatement, but I educated myself on the basics: IIC, STC, and the ratings of different products in different arrays. You can't just go for "well, that worked for me" as a basis of making an informed recommendation. Thousands of window contractors install windows wrong every day because it's what's worked for them in the past--and 95%, it doesn't fail even when done badly. But that doesn't mean it's a good way of doing things.

    I'm not a Green Glue shill, but I'm a penny watcher, and this is one case where the cheapest solution is head and shoulders the best, so I crow it--as an educated user!

    >Would any of the above apply when the sound is coming from overhead? My upstairs full bath is right over the kitchen. Hope this is not TMI, but when someone up there takes a leak, everyone in the kitchen has the urge to put up an umbrella. I swear the sound is somehow magnified. So when I have the bathroom renovated, is there any way to muffle the sound between floors?

    THIS case is probably mostly due to a low STC (through air) rating rather than the IIC (through framing) rating.

    The "dumbest" solution is that 1.8 gal toilets have a smaller water spot and so are less prone to being noisy than 3+ gal toilets. So if you have a 3+ gal flush now, all it may need is a switch over to a better-designed toilet. Quiet-peeing toilets are sometihng I've never looked into, but I'm sure there are plenty of people who have recs here!

    My first suspicion would be that there is a direct passage of sound. I have a feeling that there are penetrations in the floor that aren't foamed or--even better--caulked with Green Glue's caulking. There's probably space around the toilet flange.

    Insulating the joists--with either regular or soundproofing insulation (the soundproofing insulation is really just marginally better) will help airborne sound, too.

    My second suspicion would be IIC--that the sound is traveling through the toilet bowl, through the tile, and to the structure of the house. From above, your options are limited:

    1) Isolate the sound at the bowl by installing the toilet on a thin cork "lift," hidden behind the caulk.

    2) Isolate the sound at the floor by switching from tile to a resilient floor like vinyl or wood. (I'm not saying all solutions are smart for a bathroom--this is just what's possible.) Adding rugs NOT under the toilet won't help.

    4) Isolate the sound at the subfloor by adding joist tape. (It only helps a little, so if you don't have to take up the subfloor, don't do it for this.)

    5) Add mass. A self-leveling underlayment of a good 1/2" plus tile would be something. I hate Mapei's. FWIW.

    Raising the walls to a high STC will help with the IIC somewhat, too, as sound enters walls through the air and is transferred to the structure. For that, I'd recommend Green Glue sandwitched between a double layer of drywall. If you really want to go whole-hog, mount the sandwitch upon resilient channels, but that will raise your cost substantially, though it's the next cheapest AND next most effective thing, if you want to leave your surrounding rooms untouched. A solid-panel door will be quiter, too.

    Remember to foam/Green Glue caulk all the wall penetrations, too, in ANY case.

    This taps out what you can do from the top--or at least everything I can think of!

    From the bottom, you can either add a layer of sheetrock over your current ceiling with Green Glue in between (note that it isn't an adhesive--you have to use fasteners) OR rip down the current sheetrock, install resilient channels, and install a double layer of sheetrock with Green Glue between. Under no circumstances should you install a resilient channel OVER existing sheetrock. It will make your acoustical problems worse in the high (common) frequencies that cause standing waves between the layers.

    You could change your waste stack to iron, but if it isn't the flushing that's bothering you, it won't help with anything else.

    The strategies for soundproofing are as follows:

    1) ABSORB sound. Soft things like carpet absorbs impact well. For airborne sound, soft things like insulation do a rather poor job, but they're cheap. High mass (cement) and visoelastic (Green Glue) dampening both dampen sound, but in different ways. Mass-loaded vinyl is quite expensive and usually has abysmal STC ratings per square foot--really, you'd do a lot better to fill the cavity with concrete, if your structure can handle it.

    2) ISOLATE sound. You do this by mechanically separating the parts of the structure. Staggered studs and parallel walls do this, as do resilient channels, drop ceilings, Green Glue caulk under the bottom plates, etc.

    That's it! :-) It's just a matter of how well each thing does its duty after that!

  • johnfrwhipple
    14 years ago
    last modified: 9 years ago

    A lot of assumptions are made above as to my lack of knowledge. I know what works for me and as stated above I never gave every point and sub point for every type of install.

    I feel searching information on the internet is hit and miss. I take everyone's opinion and look for common ground. If I find that more people prefer working with product "X" over product "Y" I learn more about product "X".

    Who's opinion holds more weight? Do you believe the company's website info? Your buddy's ideas? Your current contractor?

    Look for a contractor with insurance, with WCB, that are incorporated and have been for at least 5 years. Look at their work. Look at their references - you are about to put them in charge of thousands of dollars.

    My references and insurance information is available online. It won't take much searching to find out more about me and my North Vancouver company.

    I love the debate and love the fact that so many are so passionate about their specific niche. I'm spoiled as I work in the upscale luxury bathroom and fireplace market. Our projects range in price from $200.00 to $800 + dollar's a square foot - all in.

    I will read more about Reyesuela's products and look further into this. If we where doing a larger soundproofing job perhaps these cheaper opinions will make more sense from a budget point of view.
    Don't believe everything you read online and if you find the right product or system find other's that agree. Then check with your local building department.

    I hold a Vancouver's business license and work with city inspectors all the time. I know what works from first hand experience on my jobs. And can only offer my opinion - and that is of a Bathroom Fireplace renovator not a sound proofing specialist.

  • davidro1
    14 years ago
    last modified: 9 years ago

    Good answer, jfrw.

    Soundproofing depends a lot on how thorough you are.
    The final result depends on you not on the product.
    Example: "... caulk under the bottom plates..."
    A layer of dampening, a layer of mass, etc, each being airtight.

    The OP said ".... all we find at Home Depot is a ..." and I think it's good to point out that Home Depot or any big chain is going to sell a limited subset of what is available, and there are a number of reasons for this, all commercial, none moral, none right. It has long been known that these chains will sell you anything that is "good enough" as long as they can avoid being targeted as scandalous. Without much regard for what is the RIGHT thing to sell for a specific application, they will sell what they can get from a supplier under commercial contracts that suit their logistics and profits. If I owned a big chain I would have the same dilemma but I might still manage sometimes to bring the RIGHT product to market too, or put a lot of pressure on the suppliers to get it right....

    It has taken far too many years to get products that help soundproof rooms.
    It has taken far too many years to develop "common knowledge and practices" about sealing perforations to help soundproof rooms.
    Same thing for airtightness for insulating the building envelope against heat and cold.
    My opinion.

  • johnfrwhipple
    14 years ago
    last modified: 9 years ago

    {{gwi:1408560}}

    {{gwi:1408562}}

    The batt insulation is Roxul's 'Safe N' Sound' and you can see the styrofoam shipping containers that Dornbracht suggests that get kept on for the installation.

    Add on 1/2" concrete board, Kerdi and Tile and you have a nice quiet wall...

  • lazy_gardens
    14 years ago
    last modified: 9 years ago

    "the styrofoam shipping containers that Dornbracht suggests that get kept on for the installation"

    Brilliant!

    Also, if you can't add mass to the bathroom side of a wall, add a double layer of sheetrock or use extra-thick in the room on the other side of the wall.

    We had a noise problem with a dishwasher in the end of a peninsula, and gluing 3/4 inch sheathing to the rear and side of its enclosure cut the noise significantly. Had we been thinking, we would have had the contractor do a double-thick section when he made the cabinets.

  • tracey_b
    14 years ago
    last modified: 9 years ago

    We're building a new home, and I am also wanting to make the master bath as soundproof as possible since hubby gets up too early for me.

    We're using approx. 1/4" spray foam insulation on our outside walls (in addition to regular insulation), and I'm wondering if having them spray the interior bathroom walls will help with soundproofing or be a waste of money (the spray foam isn't cheap). Any thoughts?

    They're ready to insulate this week.....

    Thanks!
    Tracey

  • davidro1
    14 years ago
    last modified: 9 years ago

    yes, a continuous layer.

    is the door nearby to whoever is asleep?

  • kathleenca
    14 years ago
    last modified: 9 years ago

    We used batting insulation between studs when we had the walls open, & it really helped a lot.

  • johnfrwhipple
    14 years ago
    last modified: 9 years ago

    I sprayed 4000 board feet of 2lb foam at my home project a few weeks back. I asked the spray boys this question and they suggested wrapping the pipes with some sort of pipe wrap instead of just foam.

    You will find if you seal up the air spaces and add more mass like Roxul's Safe n' Sound, CBU, waterproofing and tile you will get a much quieter room. If a stud cavity is out of control with pipe or wire you can't insulate it very well and this is where spray foam goes a long way. Most spray outfits need you to order at least 800 board feet before it's cost effective for you. Many kits are available and I think Brian from HGTV uses Tiger Foam on occasion.

    Look into Quiet Rock - it is that good!

  • soggydollar
    14 years ago
    last modified: 9 years ago

    We used Cocoon on all the interior walls around the bathroom. It is so quiet and very cost effective.

  • buyorsell888
    Original Author
    14 years ago
    last modified: 9 years ago

    DH takes offense that I think he is noisy in the bathroom. He isn't going to go to any huge efforts to sound proof. I may get some fiberglass batt insulation shoved in the wall and that is it. :(

    I have seen Mike Holmes use the wrap stuff on electrical boxes and such on HGTV but do not know where to buy this in the USA. We have been to independent retailers as well as Home Depot and aren't finding much. We don't have a contractor. DH is doing all the work. I prefer to buy form independents over big boxes and will if at all possible.

  • davidro1
    14 years ago
    last modified: 9 years ago

    If the bathroom is between both bedrooms, you will still hear noise coming thru the doorway. It's so close.

    Preventing noise from coming through the wall is going to make the noise travel pattern more standard, more traditional and and therefore more acceptable to the average person. Yes, we all know that the only person to please is you, not the next buyer who may never notice this when they come look see and inspect.

    Perhaps this description is all you need to convince DH to tape around the electrical outlets and to add a Roxul or equivalent high mass high absorbency padding in the stud cavities. A better product than the old run of the mill pink or yellow scratchy fiberglass batts will make a small improvement (although anything is better than nothing). There are other products no doubt being sold in your local stores that are better than fiberglas batt stuff. Good luck in finding them. Perhaps the web site of your local stores will be the best place to start. Post again once you have found something.

  • tedwhite
    13 years ago
    last modified: 9 years ago

    When were looking to soundproof a partition (wall or ceiling) weÂd like to introduce Absorption in the otherwise hollow wall or ceiling cavities. Foam is a common consideration, but not appropriate for what we want. For damping the resonance in the air cavity, we prefer medium density fiberglass, cellulose, mineral fiber or polyester. All of these are open and 'airy' enough to adequately interact with the sound waves.

    Foams are not adequately open. 'Open cell' foam is certainly better than closed cell foam, but not as high performance as something like fiberglass. Additionally, foam can couple the two sides of a wall or floor, allowing much better conduction of the vibration from surface to surface.

    Foams are superior from a thermal perspective, but not a sound isolation perspective.