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In this Instructable, I'll demonstrate how to soundproof a wall using a method I developed for my home recording studio. It is similar to the resilient channel method, but it is has advantages of being 1. much cheaper, 2. much sturdier, 3. allows the possibility of securing shelves or heavy items to the wall, 4. is removable in case you'd like to tweak something about it, and 5. uses ordinary 2x4 lumber that requires no special-ordering and associated shipping costs. Compared to the resilient-channel method, one wall can be soundproofed to the same degree as the resilient-channel method for about a fifth to a third of the cost. Sturdiness can be adjusted to your needs - for extra precaution, you may simply "use more". (For reasons I'll describe, I prefer to use as little as I can get away with.) And completely unlike the resilient channel method, you can drill holes in it (!) to secure heavy items such as shelves or cleats to hang acoustical panels and the like.
The trick to this method is that the drywall panels are hung on a pair (or more) of wooden "cleats" made from a sliced 2x4. The upper cleat on the back of the drywall is isolated from the lower cleat on the wall behind by inexpensive closed-cell foam tape. No part of the outer and inner walls touch directly. In practice, very little sound is transmitted through the foam, and the walls achieve a very high degree of soundproofing. The weight of the drywall keeps it in place so surprisingly well, that I use only two cleats: one near the top and one across the middle.
Overall, this method is fairly easy. It's not nearly as quick as using resilient channel, because it involves splitting a 2x4 lengthwise. (In either method, you will want to use foam tape to add extra soundproofing, so this extra step isn't a tradeoff, unless you choose to buy the resilient-channel pre-taped. The parts list is very small - drywall, a table saw or bandsaw, one 2x4 for every 4x8 drywall panel, nails, drywall screws, foam strips, and some pipe insulation. Surprisingly, this method requires much less precision than you would think, because some mistakes are in a sense self-correcting. Of course, the DIY version of this method does assume skill and confident use of limb-shearing power tools to do a potentially-dangerous "rip cut". If you don't have a woodworker's confidence with this step, find someone who can do it for you. A great recommended alternative is to have the lumberyard cut the wood for you upon purchase. In the section on ripping the wood, I'll tell you what to say to get the cut we want.
Since soundproofing carries with it a lot of myths and misconceptions, this Instructable will start with a little soundproofing theory before heading into the steps.
The trick to this method is that the drywall panels are hung on a pair (or more) of wooden "cleats" made from a sliced 2x4. The upper cleat on the back of the drywall is isolated from the lower cleat on the wall behind by inexpensive closed-cell foam tape. No part of the outer and inner walls touch directly. In practice, very little sound is transmitted through the foam, and the walls achieve a very high degree of soundproofing. The weight of the drywall keeps it in place so surprisingly well, that I use only two cleats: one near the top and one across the middle.
Overall, this method is fairly easy. It's not nearly as quick as using resilient channel, because it involves splitting a 2x4 lengthwise. (In either method, you will want to use foam tape to add extra soundproofing, so this extra step isn't a tradeoff, unless you choose to buy the resilient-channel pre-taped. The parts list is very small - drywall, a table saw or bandsaw, one 2x4 for every 4x8 drywall panel, nails, drywall screws, foam strips, and some pipe insulation. Surprisingly, this method requires much less precision than you would think, because some mistakes are in a sense self-correcting. Of course, the DIY version of this method does assume skill and confident use of limb-shearing power tools to do a potentially-dangerous "rip cut". If you don't have a woodworker's confidence with this step, find someone who can do it for you. A great recommended alternative is to have the lumberyard cut the wood for you upon purchase. In the section on ripping the wood, I'll tell you what to say to get the cut we want.
Since soundproofing carries with it a lot of myths and misconceptions, this Instructable will start with a little soundproofing theory before heading into the steps.
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Signing UpStep 1Soundproofing Theory
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First I'd like to 1. clear up some basic soundproofing theory, and 2. explain some typical alternative methods.
"Soundproofing" (as distinguished from acoustical treatment) is concerned with blocking sound.
You block sound with 1. mass, and 2. isolation.
Putting foam or other absorptive things on the inside of the wall is not soundproofing, but acoustical room treatment, which is used to reduce echoes and resonances and prevent excess sound buildup within a room. Soundproofing and room treatment are completely different things. Room treatment improves the sound within the same room. Soundproofing is about preventing sound from getting out or in. Definitely, putting foam on the walls can help keep your neighbors from calling, but it's not because of "soundproofing" -- it's because you have treated your room and in effect "turned down the volume" like they asked you to do.
Soundproofing a wall involves the principles of mass and isolation. A heavy wall will soundproof better than a lighter wall of the same construction. BUT isolation is the trick that will let you achieve the same results with a lighter wall.
A traditional wall involves panels (drywall, siding, stucco) connected to a frame, with drywall attached to the inside. There is usually fiberglass insulation inside the wall. It can typically block about 30dB of sound if constructed tightly. The way it works is mainly through the mass of the wall (drywall + frame) with some absorption by the insulation (effectively "turning down the volume") in the little "room" between the panels.
You can make a better wall by finding ways to isolate one panel from the other. In the staggered stud method, the vertical studs are staggered in depth so that the front and back panels are screwed into different sets of studs. However, they are still attached to the same top and base board of the frame, so some sound will travel straight through.
The ultimate method involves "double wall" construction. You essentially create a room inside a room with no part of the inside wall touching any part of the outside wall. Double walls can block in the range of 55-60dB of sound. A disadvantage is that the extra wall thickness can eat up a lot of space within a small room.
In between these two extremes, there is the resilient channel method, which involves attaching springy metal strips to the studs of the outside wall, then screwing drywall into a flange on the strips in such a way that the wall can flex against the resilient channel without touching the outside wall's studs. When constructed properly, these walls can block into the 50dB range. Other implements can be added to the resilient structure to get into the high 50dB range, such as foam tape and varieties of "isolation clips" that are clever ways to attach the channel to the studs without screwing directly. Of course, the cost of these adds up quickly.
My method is also in between the single and double wall construction, and it is similar to the resilient channel method in creating a "springy" wall that will flex. Unlike the standard resilient channel method in which the channels are screwed into both the stud and the drywall, in my method there is no direct mechanical path from the outside wall to the inside wall. So my performance should be most comparable in soundproofing capability to resilient channel methods with isolation clips. (Exactly how close we come remains to be verified by testing however, so stay tuned for future revisions of this instructable.) I will say, however, that it's "pretty darned good".
Of course, if you're running a commercial operation or otherwise have the funds, definitely look into a well-documented industry-standard soundproofing method like resilient channel or double-wall construction. They've been studied and measured thoroughly, and there's little mystery about why they work and how well they work. But if you're desperate and/or short on funds like many musicians, this method could be just what you need to get excellent results without a lot of investment.
For more information on soundproofing, especially technical aspects of soundproofing and studio acoustics, I recommend F. Alton Everest's books Master Handbook of Acoustics and Sound Studio Construction On a Budget. For non-technical soundproofing advice (mixed with a lot of product hype) see Soundproofing.org, (which I am compelled to point out I have no affiliation with and am generally critical of, even though, quite coincidentally, they are local to me.)
First I'd like to 1. clear up some basic soundproofing theory, and 2. explain some typical alternative methods.
"Soundproofing" (as distinguished from acoustical treatment) is concerned with blocking sound.
You block sound with 1. mass, and 2. isolation.
Putting foam or other absorptive things on the inside of the wall is not soundproofing, but acoustical room treatment, which is used to reduce echoes and resonances and prevent excess sound buildup within a room. Soundproofing and room treatment are completely different things. Room treatment improves the sound within the same room. Soundproofing is about preventing sound from getting out or in. Definitely, putting foam on the walls can help keep your neighbors from calling, but it's not because of "soundproofing" -- it's because you have treated your room and in effect "turned down the volume" like they asked you to do.
Soundproofing a wall involves the principles of mass and isolation. A heavy wall will soundproof better than a lighter wall of the same construction. BUT isolation is the trick that will let you achieve the same results with a lighter wall.
A traditional wall involves panels (drywall, siding, stucco) connected to a frame, with drywall attached to the inside. There is usually fiberglass insulation inside the wall. It can typically block about 30dB of sound if constructed tightly. The way it works is mainly through the mass of the wall (drywall + frame) with some absorption by the insulation (effectively "turning down the volume") in the little "room" between the panels.
You can make a better wall by finding ways to isolate one panel from the other. In the staggered stud method, the vertical studs are staggered in depth so that the front and back panels are screwed into different sets of studs. However, they are still attached to the same top and base board of the frame, so some sound will travel straight through.
The ultimate method involves "double wall" construction. You essentially create a room inside a room with no part of the inside wall touching any part of the outside wall. Double walls can block in the range of 55-60dB of sound. A disadvantage is that the extra wall thickness can eat up a lot of space within a small room.
In between these two extremes, there is the resilient channel method, which involves attaching springy metal strips to the studs of the outside wall, then screwing drywall into a flange on the strips in such a way that the wall can flex against the resilient channel without touching the outside wall's studs. When constructed properly, these walls can block into the 50dB range. Other implements can be added to the resilient structure to get into the high 50dB range, such as foam tape and varieties of "isolation clips" that are clever ways to attach the channel to the studs without screwing directly. Of course, the cost of these adds up quickly.
My method is also in between the single and double wall construction, and it is similar to the resilient channel method in creating a "springy" wall that will flex. Unlike the standard resilient channel method in which the channels are screwed into both the stud and the drywall, in my method there is no direct mechanical path from the outside wall to the inside wall. So my performance should be most comparable in soundproofing capability to resilient channel methods with isolation clips. (Exactly how close we come remains to be verified by testing however, so stay tuned for future revisions of this instructable.) I will say, however, that it's "pretty darned good".
Of course, if you're running a commercial operation or otherwise have the funds, definitely look into a well-documented industry-standard soundproofing method like resilient channel or double-wall construction. They've been studied and measured thoroughly, and there's little mystery about why they work and how well they work. But if you're desperate and/or short on funds like many musicians, this method could be just what you need to get excellent results without a lot of investment.
For more information on soundproofing, especially technical aspects of soundproofing and studio acoustics, I recommend F. Alton Everest's books Master Handbook of Acoustics and Sound Studio Construction On a Budget. For non-technical soundproofing advice (mixed with a lot of product hype) see Soundproofing.org, (which I am compelled to point out I have no affiliation with and am generally critical of, even though, quite coincidentally, they are local to me.)
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I am planning to do up my studio with Quietrock.
I heard that QuietRock is excellent for soundproofing walls. I found some interesting information on their site http://www.quietrock.com/educational-resources/soundproofing-home-theaters-and-media-rooms.html
It will take me some time to do it myself. Thanks for all the tips.
Different ideas on how to isolate sound are common, but really decoupling, damping, mass, and absorption are the only real true ways to isolate sound. Double stud wall with mass and damping (Green Glue, Decibel Drop, Quiet Glue, etc.) is really the only way to go. Little tricks and fixes really only add minimal benefit to isolation.
If you want to talk more about sound isolation feel free to stop by www.soundisolationstore.com. We would be glad to give you honest and free advice about using products like Green Glue, resilient sound clips for mimicking double stud/staggered stud walls, or even just advice on framing double stud/staggered stud walls.
I've considered a folding wall for a second wall. A difficulty is "where to put it" when the door is open. Since it would want to be taller than the garage door, the only way to move it out of the way would be to push it halfway into the room, right? It MAY be possible to push the accordion off to the side, like they do for conference rooms, if I have space over there. A weirder solution would be to make panels that fold down, so that the garage door could open over it. That's kind of funny to think about. Imagine having a wall inside the garage door with a wide door in it: You roll up the garage door and go in the smaller door. The only reason to open the garage door anyway is to move furniture in and out, and to refresh the air. Otherwise I go in the side door. Hmm.... stuff to think about, measurements to be made.
Is there a way to 'soundproof' or "sounddampen" without having to remove the drywall, say in the case of a renter?
BUT assuming you have a windowless room and don't mind some construction, you would essentially build a room inside that room. With clever engineering, it's conceivable to support the walls and ceiling and do it in an unobtrusive way, even with portable sections. You could start by framing individual 4x8 panels (or even 4x4 panels) and bolting them together. Insulation goes behind. The ceiling would be a challenge.
Of course, if you could get the owner in on it, that changes things. The hottest innovation in soundproofing is Green Glue which is a viscoelastic polymer than you sandwich between drywall panels. The claims are that a few layers of the Green-Glue+drywall sandwich can get a windowless room into the recording studio range of quiet. It's not cheap, but for convenience and ease of application, it's a godsend.
Soundproofing requires mass. (See Slide 2 on "theory") Egg cartons have little mass and do not block sound. While they do absorb and diffuse reflections, the effect is tightly centered around a certain frequency, which leaves a "bad-sounding" room.
Fact: Soundproofing must be HEAVY and airtight. So anything either lightweight or filled with holes -- spongy foam, styrofoam, carpet, thin panels, plastic sheeting -- have little to no soundproofing properties on their own.
These all have uses in "acoustical room treatment" -- for dealing with reflections and resonances -- but they must be applied in the right way, knowing their absorption characteristics and where to apply them for best effect. (ex. many absorbers don't do all that much when you stick them flat on a wall!)
For inexpensively soundproofing a music room -- that is, blocking sound to keep desirable sound in and undesirable sound out -- there really are no "tricks" that don't involve some variation on *drywall*. Your only real choice is "How are you going to attach the drywall?"
I use a mylar coated bubble wrap to line insides of vans and it does a great job of soundproofing its very light (maybe 5 lbs to do entire van) and only 3/8" thick.
i used it to line the inside of a longneck beer box set box over my rock tumbler just so i could sleep in the same room .
stuff i use i get from shipping co used in refer trucks but same stuff as this is http://www.acehardwareoutlet.com/(az54ikv0wey2bzj4psw2mw45)/productdetails.aspx?sku=8163602&source=GoogleBase
Soundproofing vehicles like vans and airplanes is a whole different mess than building a recording studio. The level of noise that is considered "quiet" in vans and airplanes would be intolerable in a recording studio. In vehicles, soundproofing needs to be lightweight, and there are great solutions for that. But for recording purposes, lightweight doesn't cut it -- amplified microphones pick up everything.
re Diffusion, egg cartons are too regular to be a suitable diffuser for most purposes. The diffusion effect is constrained around a certain group of high frequencies whose wavelengths are similar in size to the depth of the cartons, and the effect is irregular. Much better diffusers can be made more cheaply and more conveniently by using regular cardboard and following RPG-style principles, using number theory. I'll post an instructable someday on this.
re: egg-crate foam - Keep in mind the difference between soundproofing and room-treatment (see page 2 of the instructable.on "soundproofing theory"). Foam on the walls is "room treatment" and it's great for "turning down the volume" within the room by absorbing higher-frequency reflections. It "dulls" the sound. But open-celled spongy foam does not *block* sound - which is what soundproofing is about. For actual soundproofing, you need solid reflective mass.
That said, I love finding leads on cheap acoustical foam for room treatment. An important consideration is the density of the foam. The lighter foam usually used for mattress toppers isn't dense enough to absorb all that much, but it's still useful when that's what you need and you know how to use it to best benefit. I'll do an instructable on acoustical paneling at some point. Ultimately you really don't want foam all over the walls, because it makes the room too "dead", and usually in a very irregular way - instead you want just a few strategic places, at primary reflection points.