Green Room Recording Studio in Virginia, USA.

I plan to start building a studio in my garage (which is attached to my house) in approximately six weeks. The budget for materials is around $4,000. A large concern is sound isolation for sound leaving the space (especially the recording booth). Ideally, I’d like to be able to record a drummer in the middle of the night without disturbing my neighbors (the nearest one is about a hundred feet away). Another issue is ventilation/HVAC. I’ve already been through a decade of turning off a portable AC (in the control room) and suffering for sound quality. I’d really appreciate some help in making this a comfortable space that won’t anger the neighbors! What would be the best way to do the HVAC? I’ve read a lot about using an AC window unit, and have that open into a “cooling room”. If we elevate the booth and control room floors, could we use that as the “cooling room” and vent up through the floor? Alternatively, there is an attic above (in the existing structure) that could be used for ventilation/cooling. Instead of having an AC unit for each room, could we mount a separate fan to the duct work to each room, and wire them with a separate speed and/or separate on/off switches to keep each room at the desired temperature? The central air system for my house needs to be replaced and ducts could easily be extended over to the attic above this space. (Garage ceiling height is 10’ 7”) Should I do this or keep it completely separate? Perhaps multiple "zones" could be used to set the appropriate temperature for this space? Thank you all very much for any help you can offer, I really appreciate it!

Hi, just a few quick points. 1) to achieve good isolation you will require a 2leaf system. so your iso booth and control room will have to be two seperate rooms. In your design you have them joined with the walls going width ways across the garage. 2) i would personally remove or resize the window in the control room so its not within you first reflection points, atleast have a small one next to the door. Then you can use that wall to add treatment to match what you'll do on the exterior wall side. Basically you have to make it symmetrical, atleast until your past your mix position. 3) you will require another wall across the side that backs on to the cars to create a fully 2 leaf wall design. if you have a look at both the iso/vocal booth designs and the component parts system, you should be able to get a better idea of what your aiming for. http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=5457 component link http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=14147 booth http://johnlsayers.com/Recmanual/Pages/STC%20Chart.htm this link shows you the difference of isolation to wall construction, higher the better :D hope this helps

leon.payne wrote:

Hi, just a few quick points. 1) to achieve good isolation you will require a 2leaf system. so your iso booth and control room will have to be two seperate rooms. In your design you have them joined with the walls going width ways across the garage. 2) i would personally remove or resize the window in the control room so its not within you first reflection points, atleast have a small one next to the door. Then you can use that wall to add treatment to match what you'll do on the exterior wall side. Basically you have to make it symmetrical, atleast until your past your mix position. 3) you will require another wall across the side that backs on to the cars to create a fully 2 leaf wall design. if you have a look at both the iso/vocal booth designs and the component parts system, you should be able to get a better idea of what your aiming for. http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=5457 component link http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=14147 booth http://johnlsayers.com/Recmanual/Pages/STC%20Chart.htm this link shows you the difference of isolation to wall construction, higher the better :D hope this helps

Hello, leon.payne. Thank you for your reply. I've tried to edit my build slightly to meet your recommendations. 1 & 3) I separated the booth and the control room and then added an additional frontal wall, as well as additional doors to compensate. 2) I've removed the window and replace the door with two sliding glass doors. I do have a few more questions, if you or someone else wouldn't mind asking. 1) How much air space do you think would suffice between the walls? 2) For all the walls we are going to be using drywall (with insulation behind it) for interiors. So, for that additional (newly added) leaf/wall, would we want to have drywall facing the "cars" or just plywood? What layering would give us the best advantage? 3) Would this design work better than using staggered studs? Thank you again for your time.

Hi "ErroneousDylan", welcome! :)

I've tried to edit my build slightly to meet your recommendations.

That looks much better. However, the control room seems to be almost square, which is not good. What are the dimensions of the interior? You show 11'4 length, but it's not clear what the width and final interior height will be, after isolating the ceiling.

1) How much air space do you think would suffice between the walls?

That depends on how much isolation you need, how low you need to cover (down to what frequency), and the amount of mass that you intend to have on each side. The minimum recommendation is 4" of air gap: less than that and you start to lose isolation, plus your resonant frequency starts to get too high to be useful. 8" of air gap is pretty good, assuming that you have plenty of mass on your leaves.

2) For all the walls we are going to be using drywall (with insulation behind it) for interiors. So, for that additional (newly added) leaf/wall, would we want to have drywall facing the "cars" or just plywood? What layering would give us the best advantage?

I'm not quite sure I understand you: If you are only going to use drywall, then where did the plywood come from? Assuming you plan to use one layer of plywood plus one layer of drywall to build up each leaf, then the plywood goes on the studs first, with the drywall going directly on top of the plywood. If you are asking if it is better to build your walls "conventionally" or "inside out", then that depends on what you are trying to accomplish. Acoustically, it makes no difference which side of the leaf you put the studs on. If the mass is the same and the air gap is the same, then the location of the studs makes no difference, from the point of view of isolation. There might be structural, practical or aesthetic reasons for choosing either conventional or inside-out construction, but it doesn't have much effect on isolation.

3) Would this design work better than using staggered studs?

Is the garage already built? If so, then you don't have the option of staggered studs, except on the new isolation wall that runs across the end of the garage. Staggered studs will give you good isolation, but separate stud frames is a bit better. Also, using staggered studs for that new wall implies that you will be tying together the control room and live room again, which you just separated...

The budget for materials is around $4,000.

Then you might want to re-think using sliding glass doors for the control room. A pair of acoustic-rated sliding glass doors capable of stopping drums at midnight, is going to eat up your entire budget, leaving you with nothing left to build the rest.

What would be the best way to do the HVAC? I’ve read a lot about using an AC window unit, and have that open into a “cooling room”.

The more common term for that concept is "exchange chamber". You could do that, but do you have a room next door that you could use for that? Maybe the garage itself?

If we elevate the booth and control room floors, could we use that as the “cooling room” and vent up through the floor?

If you elevate the floor, then you create a resonant cavity below your rooms: in other words, you make your floor into a drum head, that will ring, resonate and vibrate along with the music. Not a good idea. That will also have severe consequences for your isolation.

Alternatively, there is an attic above (in the existing structure) that could be used for ventilation/cooling.

That sounds like a good possibility, but it might be easier to just do a more conventional HVAC system, with a couple of mini-split units for the actual heating/cooling/dehumidifying, and some simple ducts, fans and silencer boxes for the ventilation.

Instead of having an AC unit for each room, could we mount a separate fan to the duct work to each room, and wire them with a separate speed and/or separate on/off switches to keep each room at the desired temperature?

If you use an exchange chamber you could go with that method, but then you need one very large A/C unit, big enough to cool and dehumidify both rooms at once when they are both at maximum capacity (maximum number of musicians in both rooms, playing as hard as they can, on a hot damp day in mid summer), then you'd still have to run that same very large unit when you are working alone in the control room at night in mid winter. So not only will your electrical bills be high, but when you are not running both rooms at maximum capacity, then the HVAC unit will be doing very short cycles, and thus will not be controlling humidity very effectively. So you might save a bit of money on one side of the equation, but then end up spending much more on the other side, and still not having good climate control.

The central air system for my house needs to be replaced and ducts could easily be extended over to the attic above this space.

If you are going to replace that, then it makes a lot of sense to get the HVAC contractor to just add some extra ducts and create two zones for your two rooms, each with its own set of electrically controlled variable dampers and fans. Then all you need to worry about is building some silencer boxes where the ducts come into and leave each of the rooms. One final point: the existing windows in the garage wall will have to be sealed air-tight in order to get good isolation. In fact, it would be better to replace each one with a new window having a with single fixed pane of thick laminated glass. You have a nice space there, so your possibilities for building a great studio are pretty good! - Stuart -

Thank you very much for your response, Stuart! As per usual, I have a few more questions that I hope you won't mind taking a look at.

That looks much better. However, the control room seems to be almost square, which is not good. What are the dimensions of the interior? You show 11'4 length, but it's not clear what the width and final interior height will be, after isolating the ceiling.

I'm sorry I didn't clarify in my blueprints about the width of the control room. It is equal length with the isolation booth at 10' 6". As for the height, nothing is set-in-stone at the moment and is completely negotiable. The height of the existing garage is 10' 7". I wasn't sure if I'd be doing the raised floor concept (hence why I ran it by you guys first). Also, I hadn't planned for a specific floor or ceiling thickness, nor do I know what shape would be best for the ceiling. I was hoping you guys could suggest something for it. In this model that user "leon.payne" linked me earlier http://johnlsayers.com/Stuff/Small_Studio.skp, I noticed that the ceiling of the control room is angular but the isolation booth just has a flat ceiling (at least from what I can see in the model). I would imagine it wouldn't really cost any more to angle a ceiling so would there be a problem doing it the isolation booth as well? Also, yes my current design of control room (and isolation booth) are plainly square. I've considered making some changes to the control room. For instance, in that same model I linked you, they have the speaker walls angled in towards the mixing desk. I was considering doing that, and possibly the same concept on the wall parallel to it, which would make the room more octagonal.

Then you might want to re-think using sliding glass doors for the control room. A pair of acoustic-rated sliding glass doors capable of stopping drums at midnight, is going to eat up your entire budget, leaving you with nothing left to build the rest.

Mainly, I am only worried about isolation in the booth (which wouldn’t have sliding glass doors). The control room doesn't have to be as soundproof as I would be willing to monitor with headphones during the wee hours. I figured using a cheaper set of sliding glass doors would allow me to remove my previously considered window and also give enough room to angle the corner as previously mention above. Thank you again for your response and time. -Dylan

Anybody else have anything to add?

I would imagine it wouldn't really cost any more to angle a ceiling so would there be a problem doing it the isolation booth as well?

You could if you want, but there isn't much reason to do that in an iso booth. The reason for doing it in the CR is normally as part of an RFZ system, but that doesn't apply to iso booths. Also, angling the ceiling in the booth will probably eat into your room height. If your reason for angling was to control flutter echo on the vertical plane, it's probably easier to treat that with insulation than with angling.

they have the speaker walls angled in towards the mixing desk. I was considering doing that, and possibly the same concept on the wall parallel to it,

soffit mounting your speakers is highly recommendable. It just improves so many things all round. - Stuart -