basic studio / practice room - Total newbie

Hello everyone, I have been reading quite a bit on this forum and a few others and have learned a lot. There are some very helpful people here. I am hoping you can help get me going in the right direction with my studio. I am sure these questions have been answered before, but any info would be appreciated. I posted the same info on another forum, and it was suggested that I post here as well. I live in Vancouver BC. My wife and I have bought a house that we will be moving into next month. It has an unfinished "bunker" under the garage. It is 20'x20' (9' high) with concrete walls and ceiling. I plan to divide it in half, with one half being a play area for the kids and the other half being a small studio. So the studio size would end up being about 10'x17' (after the addition of a hallway) Two of the walls would be concrete finished with drywall, the other two would need to be constructed and soundproofed. I play guitar and bass and sing. My son plays drums. We currently have electronic drums, but will be purchasing an acoustic kit once we get this room finished. Due to the space limitations, I am not planning on having a separate control room. I am not planning on doing any of the contruction myself, but hiring a contractor. My main concern is the sound proofing portion. This house will have a basement suite for my father in law and I don't want to disturb him. I want to make sure my contractor does things right, so there are no issues. Essentially this will be a new room inside of a concrete room, so there shouldn't be any issue with him hearing it, but I also want it to be pretty sound proof from the kids playroom which will be directly on the other side of the newly constructed wall. My budget is $10,000-$12,000 I know I am asking for advice on EVERYTHING and I appologize, but any info would be appreciated I have created a couple of rough sketches, but I guess they are a little too big to post. I am not sure how to change the size. i will work on that and post them Thanks

Here is a sketch of the current floor plan

Here is a sketch of what I have in mind

Hi Briguy, and welcome! It looks like you have the right basic idea, but you also have a tall order! Bass and drums are the two instruments that are hardest to isolate, and you want to play them both! :) The issue is that low frequencies are the toughest to stop, as they are very long wavelengths, and have a lot of energy in them, plus the disturbing fact that isolation only works well at high frequencies: the lower the frequency, the more mass and space you need to attenuate it. The guitar and vocals are easy to deal with: drums and bass not. In other words, what you want to do can be done, but it isn't as easy as you might think. The only way to do what you want at a reasonable cost, is (as you already mentioned) with full "room-in-a-room" construction. In other words, you will partition of the two new sides shown in your rough diagram, and then in the remaining 10x17 space you will build another room, totally isolated from the existing structure on all five sides. You will need to put a lot of mass in all of those walls, and you will need a fairly decent air gap in those walls, so your final space will probably end up something like 8 x 15 x 8, give or take a few inches. (But those dimensions suggest another issue that needs dealing with. More on that later.) I'd strongly suggest that you buy Rod's book ("Home recording studio: build it like the pros") and read through that before you do anything else. It will give you all the basics for you to be able to put together the design. (Another good book is the Master Handbook of Acoustics, by F. Alton Everest.) Bottom line: your basic plan is fine, and it is possible to do what you want, but it needs to be planned carefully if you want to isolate drums and bass. - Stuart -

Thank you for the reply and info. I will definitely get that book. I have been hearing so much about it. I think I am starting to realize that i am maybe asking for too much. When it comes down to it, I think I need to forget about isolating the room from the kids area and just concentrate on isolating it from dad's place. I think that will be much easier to achieve, wouldn't it?

Actually, it's pretty much the same thing. You can't isolate one part unless you also isolate the other. Let me explain: You cannot isolate a room in only one direction. In other words, you can't just put up an amazingly good wall on the left side of the room, intending to keep things quiet in the room on the other side of that wall. Sound wraps around small object like walls, and also flanks through the multiple paths available to it in the building structure. I often use the analogy of an aquarium: Trying to isolate a room by treating only one wall is exactly the same as trying to build an aquarium by purchasing the frame and putting glass on only one side. A one-sided room will not "hold the sound" any better than one-sided aquarium will "hold water". To isolate your room successfully, you have to treat all six sides equally (or at least five of them: the 4 walls and the ceiling, assuming that the floor is a nice thick concrete slab on grade). Just doing one side is not an option. Neither is it an option to do 4 sides really well, but the 5ht side only so-so. That would be like putting glass in three sides of your aquarium and on the bottom, but putting a piece of cardboard on the other side: that won't hold water very well either. And just like the aquarium leaking water, if your room "leaks" sound, then once it is out, it is out all over: sound leaking through the right hand wall will be heard just fine on the other side of the left hand wall, and the front wall, and the back wall, and in the room above. So you really do have to do all sides the same. It isn't as hard as it sounds (no pun intended!). All you need is ordinary 2x4 stud framing, and drywall, plus some insulation (mineral wool or fiberglass). That's it! No exotic materials or secret incantations. Any good builder can do it, provided that he works a bit more carefully than normal, and does a couple of things different from what he would normally do. The key issue is in defining your expectations realistically, and putting real numbers to things like "how loud are you inside the room" and "how quite do you have to be outside the room". The basic concept is easy: make the loudest noise you ever expect to make in there, and use a sound level meter to determine just how loud it is, in decibels. Then put the sound level meter in the location where you DON'T want to hear any noise, and measure the normal ambient level there. Subtract B from A and that is how much isolation you need. Now you have a dB figure to work from. Look at the charts and tables and things to figure out the best wall that will produce that many dB of isolation. Build it. Done! The basic procedure is simple. The difficulty comes in the details, and the hardest part of all is signing the checks.... :) So don't be discouraged! What you want to do CAN be done: you just need to set realistic goals in terms of how close you can get to your goal "B minus A" number without going over your budget. Think of it this way: anything at all that you do will be an improvement over what you have now! :) - Stuart -

Thank you very much again for taking the time to reply to my post. What I meant by changing my plan was that initially I was wanting/ expecting to be able to sound proof the music room from the kids play are a directly beside it. Now I think the kids will have to put up some noise, but the main objective would be to isolate it from dad's suite, which is much further away and separated by more space and walls, including the concrete wall. In reading online, I have been looking at the diagrams on this site - http://www.soundproofingcompany.com/sol ... ing_walls/ I was thinking that the STC 66 would be the way to go, but I have no idea what the costs would be like and if it is overkill for what I am trying to do. Is it just a case of more is better ?

STC-66 would be a good figure to shoot for, but is it enough for YOU? Or too much? That's why you need to actually measure the levels. For example, set up a good full-range speaker system in the space that you have right now, before you do anything to it, and pump out something with heavy drums and bass, at about 115 dB (which is REALLY LOUD, but is roughly the level of an acoustic drum kit played fairly hard). Wear ear protection while you do this, and maybe kick everyone out of the house, and warn your neighbors that you are just testing for a few minutes. So play your heavy drum-and-bass track at 115 dB measured in the room (C-curve, slow response). Now go to your Dad's room, and measure the level there. While you still have the meter in Dad's room, slowly turn down the level of the "heavy-drum-and-bass" track until the level in Dad's room is acceptable, and make a note of the new reading on the meter. The difference between the two will give you a rough idea of how much isolation you need. Say for example that you measured initially in Dad's room at 110 dB, and then decided that 50 dB was an acceptable level as you turned it down: 110-50 = 60, so you need AT LEAST 60 dB of isolation to achieve your goal. (That's just an example: You have to do the real test yourself, in the real location with real music and a real meter.) Ok, so this isn't a great or particularly accurate way of doing it, but it gives you an idea. Also, there is the issue that STC is not a good way of measuring isolation: the method for measuring STC does not consider low frequency sounds, such as drums, bass, keyboards, and such. It was originally designed as a measure of speech isolation, not music isolation. So it tells you something about how well you are isolating, but not everything. It is quite possible to have two very different walls, both rated at STC-60, but with one of them you can hear music thumping through clearly, and with the other it is hardly audible. The REAL way to measure how well a wall isolates is with TL (Transmission Loss). It is similar to STC, but not the same, and does take into account low frequencies. So I'd suggest that you start out by getting a sound level meter, doing the tests, and figuring out how much isolation YOU think is acceptable for YOUR build. Nobody else can tell you what is "good" or "bad", since it is your space. You are there in it, we are not. Why I consider "acceptable" in Dad's room might not be the same as what you consider acceptable, which might in turn be different from what Dad himself considers acceptable. The link you show is one way of doing it, and the basic design is what I already outlined for you. It is commonly called "two-leaf" isolation, and also "Mass-Spring-Mass" (abbreviated MSM), as well as often incorrectly called "Mass-Air-Mass" (abbreviated MAM). Alaso called "room-in-room" construction Basically it means that your complete wall consists of two surfaces, or two "leaves", each of which is made up of one or more layers of something massive and rigid, like drywall, plywood, MDF, OSB, steel, lead, etc. Between these two leaves of mass is an air gap that is also filled with insulation (fiberglass or mineral wool, generally). That's the "spring" part. The two leaves are also totally "decoupled", meaning that there is absolutely no mechanical connection between them: each is built on it's own framing (ordinary 2x4 or metal framing). The materials are ordinary common building materials: nothing exotic or fancy is required. Plain old 2x4 studs, 5/8 drywall, fiberglass insulation, nails, etc. The only difference is in the method. Any framer can do it, if he is careful, and once he learns a couple of basic new rules that he doesn't normally need to follow. It isn't hard to do. The only thing that changes to increase the isolation is the amount of mass on each leaf, and the "spring" (air gap) in between. More mass means more isolation. Bigger air gap means more isolation. It's that simple. So the real question is, basically how many layers of 5/8 drywall do YOU need, and how big an air gap do YOU need, in order to get the level of isolation that YOU think is acceptable? See? It isn't hard to do this! Just follow the procedure, and you'll get there. - Stuart -

WOW. thank you so much for that post. That was one of the most informative thinsg I have read about the subject. I really appreciate you taking the time to write that all out. And it makes so much sense. Perhaps you can answer a couple of other questions I am struggling with. I am trying to decide on flooring for inside this room. I was thinking of wood laminate. I initially thought I would do carpet to help absorb some sound, but I have since read that carpet is not a good idea to capture a good room sound. If I did go with laminate, would I need to do the floating floor idea, since it is a concrete floor ? Also, for air ventilation, I will be running a duct from my furnace / AC. Is there some type of baffle system that needs to be installed in the duct to prevent sound travel to the rest of the house ? I dont have to worry about it going to dad's suite, because it is not connect. He has a separate heating system. Thanks again for the info

WOW. thank you so much for that post. That was one of the most informative thinsg I have read about the subject. I really appreciate you taking the time to write that all out. And it makes so much sense.

You are welcome! That's what most of us are here for: learn how to do things for our own benefit, then help others do it too. :)

I am trying to decide on flooring for inside this room. I was thinking of wood laminate.

Laminate is great. Good acoustically, good aesthetically, easy to clean, not too expensive, easy to lay. etc.

I initially thought I would do carpet to help absorb some sound, but I have since read that carpet is not a good idea to capture a good room sound.

Exactly: it isn't a good idea. Forget carpet. It is a "selective" acoustic absorber, which means that it absorbs some frequencies well, others a bit, and others not at all, basically at random. And unless the manufacturer has specifically published the acoustic absorption coefficients for the exact piece of carpet that you want to use, then you are entirely on your own as to how it will perform. The chances of it doing what you need in your room, purely by chance, are about the same chances as you winning every lottery on the entire planet all on the same day, while also getting struck by lightning right after surviving a mid-air collision between your plane and the space shuttle... :) So forget carpet. You MIGHT want to add a throw rug or two on your floor, right at the end of your build, once you have the entire thing isolated, treated and measured, if it turns out there your room is still a bit too "live" (too many highs bouncing around), but you won't know about that until you are finished. Leave it until a very last resort, and only if needed.

If I did go with laminate, would I need to do the floating floor idea, since it is a concrete floor ?

Nope. Just lay the laminate directly on the concrete (with the appropriate underlay, of course). Build a floating floor correctly is very complex, very expensive, requires a lot of careful calculations, and is very easy to get wrong. If you get it wrong, you wasted all of your effort, time and large piles of money. For example, if you put too much mass on the springs, then they "bottom out", the floor doesn't float at all, and you end up flanking. If you don't put enough mass on the springs, then they are not compressed at all, the floor doesn't float at all, and you end up flanking. Either way, you just built a very expensive resonant cavity under your floor, which will boom out merrily, right along with your music, screwing it up badly and making things WORSE than if you had never even tried. There's about a million and forty seven ways to float a floor wrong, and only one way to float it right. But if you are interested in floating your floor, then take a look at these two links below. They explain how to do it right, in detail. viewtopic.php?f=2&t=8173 http://www.nrc-cnrc.gc.ca/obj/irc/doc/p ... /ir802.pdf If you decide not to float and want laminate instead, then just level your floor if necessary (it has to be very level to use laminate), put down the underlay, put down the laminate, and you will have a fine acoustic floor. Or you could leave your floor as plain concrete, which is also great for acoustics. If you look around this forum, you'll see several folks who have done very beautiful and artistic things with their plan old concrete floors in their studios, with various types of stains. Some are quite awesome. Once again, it's a personal choice thing: if you like concrete, that's great. If you don't like it, then laminate flooring is fine too. So is ceramic, hardwood, etc. Anything solid, hard, rigid and acoustically reflective is OK for the floor. But not carpet.

Also, for air ventilation, I will be running a duct from my furnace / AC. Is there some type of baffle system that needs to be installed in the duct to prevent sound travel to the rest of the house ?

Yep! There are things called "silencers", which is just a fancy name for a large box with multiple dividers in it, that force the air to take a long, winding, zig-zag path through the box. All of it is lined inside with duct liner, or other isolation. Search the forum for "silencer" and you'll find more than you ever wanted to know about them. You need to put one of these in each duct (inlet and outlet), and you can also make the duct runs longer than they need to be, with several 90° bends in them, for the same reason. Ducts and vents should be over-sized (to keep the velocity low) and lined with duct liner. There are a few other things to take into account with HVAC, but that's the basic idea. - Stuart -

Again thank you so much. I have been getting a little bit discouraged and overwhelmed with this project, but I have learned more in the last few days reading your responses than I have in the last few weeks scouring the internet. I feel like I am starting to get a handle on things. Thank you for the info about the floating floor (and the humourous examples!). You have helped me decide to go with laminate. So another question I have is the ceiling. It is concrete, and it is the underside of the floor of my garage. I am not too concerned about the noise aspect, becuase it is my garage above. But what would be some ideas for finishing it ? I have read that if your floor is reflective, you should go with a ceiling that absorbs. Is this correct ? What would that mean material wise ? Or do you finish it however you want, and then treat it with acoustice absorbers after the fact ? Also, thinking about your aquarium/water analogy (which is a great way to think of things). How do you join the new wall to the ceiling and floor to prevent leakage ? I am not quite sure how to explain that question. Hopefully it makes sense. Thanks again for the great info!

I feel like I am starting to get a handle on things.

It takes a while to get your head around "things acoustic", doesn't it? I've been trying for years, and I'm still working on it... So don't feel alone. If there's one thing that I've learned about acoustics, its that nothing is logical or intuitive at first glance.

So another question I have is the ceiling. It is concrete, and it is the underside of the floor of my garage.

Concrete ceiling is GOOD! Very good. Excellent isolation.

I have read that if your floor is reflective, you should go with a ceiling that absorbs. Is this correct ?

Absolutely! In general, it's a good idea to have a soft surface opposite a hard surface. Helps with something called "flutter echo", among other things. However, your concrete ceiling isn't going to be your room ceiling... for the same reason you already suspected. See below...

Also, thinking about your aquarium/water analogy (which is a great way to think of things). How do you join the new wall to the ceiling and floor to prevent leakage ?

Simple answer: You don't! :) What you do is to install a second ceiling, which can just be plain old drywall, a few inches below the concrete, and you do it in such a way that there is no mechanical connection between the new ceiling and the existing ceiling. There are several ways of doing that. The easiest is to just put 2x4 joists across the room, resting only on your new 2x4 inner-leaf wall frames, and put the drywall on those. This has several advantages, including simplifying construction, and minimizing the possibility of cracks developing in your joints over time. This is the real concept of "room within a room": You really are building an entirely separate and slightly smaller room inside the existing room. In your case, you only need to do the walls and ceiling, but some folks really do go to the extent of doing the floor as well, in which case the entire room "floats", totally free from the rest of the building structure. That, of course, takes big money and careful planning, and fortunately is not needed in your case. Another way of doing the new ceiling is to attach special acoustic isolation brackets to the existing concrete, and hang your new ceiling from those. The issue here is that the new ceiling is not attached to the same structure as the new walls, so you have the possibility of things moving differently over time, and thus ending up with cracks around the ceiling/wall joints. Especially so if you live in a seismic zone, like me. In your case, your ceiling is a garage floor, and has the weight of cars rolling on and off of it all the time, so it would not surprise me that that constant flexing and vibration might eventually give you problems. The reason that cracks are a concern is because both your existing outer-leaf and your new inner leaf need to be sealed air-tight in order to maximize the isolation, and of course cracks in the joints means that the seal is no longer air-tight. So that's my long-winded way of suggesting that it is easier, cheaper and better for you to just put joists across the new stud walls, and hang your ceiling from that. In any event, as you suspect, you do have to do the ceiling for the same reason as the aquarium analogy: if you only isolate your walls, then the sound will "leak out" through the ceiling. And as you already figured out, there is no possible way to attached the new walls to the old ceiling in such a manner as to "keep the sound in". Just like you have to put the floor in the fish tank, you also have to put the ceiling in your room. You might be concerned that you are going to lose a bit of precious height, and for some people here that is a huge problem, but in your case you have plenty of height to start with (9 feet), so losing a few inches off that is not a big deal for you. To be very honest, you are one of the lucky ones! Not to many people here start out with 9 foot ceilings with concrete walls, floor and ceiling! That's a luxury! Some folks start out with 7 foot ceilings that are just wooden floors above them, and need beefing up drastically before they even start to think about how to´put their new inner-leaf ceiling in, and still be able to stand up in the room... Anyway, getting back to your question of how to treat the FINAL ceiling: Yes, if you have a hard floor, you need to make the ceiling "soft", meaning you can put fiberglass or mineral wool insulation up there, in one form or another. You can either attach it directly to the ceiling, or you can put it in things called "acoustic clouds" that hang down from the ceiling. There are several ways of doing that, but your basic premise is correct: hard floor implies soft ceiling, in one form or another. - Stuart -