garage to studio conversion

Hey everyone, I’m a recent newcomer to the forum and I’ve been spending most of my time studying the wall, floor and ceiling construction techniques presented here as I’m preparing to convert most of my two car garage into a single room studio. Up until now I’ve been recording my band in the family room using a Roland TD-5 electronic drum kit which of course makes recording a breeze. My drummer (a loud and heavy player) has just invested in a new double bass kit with which he is in the process of setting up in his garage temporarily until the studio in my garage is constructed. Currently our recordings are captured live with very little overdubbing. Bass, drums and guitar all go direct plus three microphones for vocals. I’d like to preserve as much as possible the live nature of our recording process once we’ve migrated into the new studio. The finished studio dimensions should be approximately 17’2” x 13’9.” This is after allowing for roughly 12” in width for each studio wall. For some reason I’m having trouble trying to attach a .BMP here for review. So far one of the biggest challenges I’m facing regards the ceiling in my garage. The garage door when open only allows me about 7’ of vertical clearance. Where the opposing wall will stand, I have 8’7” of vertical clearance. I’m guessing that I will have to build a sloped ceiling. From information I’ve gathered on other sites, it also seems that a sloped ceiling will help to control standing waves. Are there any known or potential issues concerning the construction of one of these ceilings on a slope? Tied into the ceiling issue regards gaining access to the garage door opener and the attic crawl space located right next to it. I don’t believe that I have any choice but to implement some sort of a trap door into the studio ceiling in order to gain access. The required opening should be about 48” x 32.” Would it be possible to use one of those folding stairways in the opening? Or would it totally negate the rest of my efforts?

I'm a bit short on time right now, will try to get back to this tonight sometime - meantime, if you're on a PC, try loading your BMP into paint, choose "save as", select JPG - it makes the file several times smaller, which may be your problem... Steve

Steve, Thanks for the reply. And many thanks for all of the invaluable knowledge that you've shared on this site. As you can probably make out, the garage door is at the bottom of the image. The desk in the center of the drawing is right about where the access hatch would need to be located. Bear in mind that I generally never need to gain access to either the attic or the garage door opener, but the access needs to be there just the same. The exterior walls of my home are 10" block/stucco. I have an A/C vent in the walkway behind the back wall of the studio which I will relocate when I construct the ceiling. My main concern is soundproofing the garage from my neighbors across the street. The A/C vent and return need some more thought but I want to stay focused on the ceiling for now. As far as the walls are concerned, I've been thinking about going with two layers of 5/8" sheetrock, RC, staggered studs, BATF or 703 (whichever is cheaper) and then two 5/8" layers for the outside leaf, perhaps OSB and particle board. I'm just hoping that we'll be OK with late night weekend jams...let me know if you think I should add a 3rd layer on either the outside or inside leaf. :D One other thing, I was thinking about going with 2x8 plates to create a little more spring. My thoughts were that this would also facilitate two doors (hollow?) per entry. These are my main concerns, though I am also wondering whether or not I really need to contruct a floor for this room. Thanks again -Bill

I resized your drawing to under 800 pixels wide so it doesn't force everyone to scroll sideways in order to read the text - other than that, it's 5 am here and I need to crash. Also need to know if those 10" blocks are hollow core before we get into wall stuff... Steve

Hollow-core on the blocks...it sounds like you're thinking that maybe I can use the block wall for my external leaf?

Only if you're willing to fill the cores with sand - otherwise, it's BOTH your leaves... Steve

Forget filling the blocks, that's definitely not happening. Also, the blocks are 8" in width not 10", I'm not sure if that changes anything. They are actually about 8 1/2" with the stucco. That leaves me with having to build the north and south walls which will need to attach to the block walls. Now if I'm correctly understanding everything I've read in your previous posts to other threads, the inner leaves of the north and south walls shouldn't "connect" to the block walls. Should I be thinking (is it even possible?) to attach RC along the inside of the block walls with a double layer of sheetrock in order to meet the double layers of sheetrock on the north and south walls?

Here's some solid info on sheet rock and block walls - I believe that the 190mm blocks referred to are all hollow core blocks - check out figure 5, and the associated text closely - http://irc.nrc-cnrc.gc.ca/practice/noi1_E.html Now what about that garage door; how are you gonna tackle THAT problem... Steve

Steve, I took some time this afternoon to read through the entire link regarding the concrete block walls. Based upon everything I read it seems as though I should be using 13 mm RC with a double layer of sheetrock on the inside which should produce a 54 STC rating provided that I'm using some sort of fiberglass insulation in the cavity between the sheetrock and the block wall. The other important component as you know is increasing the air cavity between the sheetrock and concrete block. Now if I were to just attach RC to the concrete wall it seems as though I would only have a cavity of approximately 1/4" in depth. According to the site I should have minimally 1 1/8" of space (when using two layers of 5/8" sheetrock). Should I consider framing out a single stud wall just to attach the RC and sheetrock to? Considering how loud the drums are going through a closed garage door I'd rather play it safe...perhaps even a 2x6 plate? Here's another thought...that site seems to indicate that even with the double layer of 5/8" sheetrock, I may still have trouble with low frequencies--I'm not sure what frequency my drummer tunes his double basses to, but he is definitely loud--should I consider laminating a layer of 5/8" sheetrock with something else that may react better to the lower frequencies? Perhaps a triple ply?

Now what about that garage door; how are you gonna tackle THAT problem... Steve

Well my original idea was that the south wall (rock,rock, RC, OSB, particle board) would run parallel 3' away from the garage door opening. (Check my diagram for this). I still want to be able to use my garage door so I'm thinking that a sloped ceiling could run downwards from the back of the garage to just under the hook that attaches the garage door to the opener. I am still going to need some type of access hatch in the ceiling. -Bill

Steve, One other thing, the block walls are sealed by a layer of plaster on the inside, maybe 3/8" to a 1/2" worth. This should help according to the link.

Yeah, given the circumstances I'd use all the air space and mass you can - if the garage door is down, even 3 feet away it will act somewhat as a third leaf and lessen your isolation, especially at lower frequencies. BTW, typical shell resonance for kick drums is around 300 hZ, but the thud from a loose-tuned kick drum head is lower than that. More like around 30 hZ I would think. Containing that will be interesting for sure - you'll need air gaps in the order of 12" or better, with at least 5 total layers of wallboard, to get decent low freq isolation. This would include a floated floor... Steve

Containing that will be interesting for sure - you'll need air gaps in the order of 12" or better, with at least 5 total layers of wallboard, to get decent low freq isolation.

In other words five layers between the inner and outer leaves combined?

Right, like 3 layers out, 2 layers in - this would make each leaf have different coincidence and mass in order to smooth out the TL curve (no common resonant frequencies on both sides of the wall) For the door - if you have room for a slanted ceiling, you could accomplish both leaves on one frame and still leave access at the front of the door - you especially don't want to close in the spring at the top of the door; when that breaks (and it will, eventually) the door guy will need good access, especially to the adjuster collars (these are at the ends of the spring, big thick "washers" with holes every 90 degrees around them - the door guy has two rods that just fit these holes, and after installing a new spring he needs to be able to "wind up" the spring to achieve balance between spring tension and door weight, so you can actually open the door. Some doors are so heavy, that when this spring breaks you need pry bars to get the door to move. I did a basic concept drawing, but left out details like number of layers, resilient mounts - it's just a start, would need refining to make sure it stays double leaf all around... Steve

I'm thinking that with 24-36" of space between the closed garage door and the face of the external leaf I'd have enough room to relocate my current workbench. I could hang my current pegboard on the exterior leaf as well and raise the garage door to access tools and such from the driveway. It's funny you mention the springs, actually I just had both of them replaced about two weeks ago, (one had been broken for the past several months). But the door guy warned me about needing access to the rollers, etc. in the event of future repairs. I figure I could always pull the workbench out for future repairs. I replaced the garage door opener a few months back. Should future replacement of the belt/travel bar become necessary I figure it could be disconnected through an access hatch in the new ceiling and then lowered in the space between the door and exterior leaf. The opening at the top of the garage door is 84". Though I haven't completely analyzed your previous posts regarding floor and ceiling construction, it looks like I'm going to lose about 18" vertically between the floor and ceiling combined which means approximately a 5'5'" door opening. Unless I can use something smaller in width than 2x6es for the floor and ceiling?

If you can somehow swing a 3.5" floated concrete slab over 2x4's on 1/2" EPDM pucks, your mass-air-mass resonance should be down around 18 hZ, without including the weight of walls or ceiling - it's not likely you can get away with less than 2x6 ceiling joists, as 2x4's are only good for a span of 9'10", even using 12" centers. You want your floor resonance as low as you can get it, 10 hZ would be a good target resonance for drums if you can get it - the resonance needs to be a couple octaves below the lowest frequency isolated, or it doesn't work well. For maximum isolation, you might be better off "stepping" the ceiling in order to maintain the most headroom in the most part of the room, instead of sloping the ceiling. Generally, your two leaves of mass for ceiling will probably end up being the addition of an extra layer of wallboard to the existing ceiling, then new joists below that (just barely) with full insulation and 2-3 layers more wallboard. Your attic is likely vented, so can't be considered as the second leaf - the fairly large volume in the attic will lessen the effect of having a third leaf, but you would still need a total of 5 layers in two leaves for good isolation of drums. Same with the walls... Steve

That slab sounds like a lot of work...do you see any other options? Or would any other options include raising the floor even higher? I had originally thought of stepping the ceiling, but I'm kind of at a loss on the design. It seems as though whether it's either stepped or sloped under the garage door, it's still going to need to be layered.

Generally, your two leaves of mass for ceiling will probably end up being the addition of an extra layer of wallboard to the existing ceiling

I had been wondering if the outer ceiling leaf should attach to the existing ceiling...let me see if I get this from the inside out. 2-3 layers of wallboard (perhaps a combination of materials here), RC?, 2x6 joists, a 1/2" of space, then a new layer of wallboard (5/8"?), attached to the existing layer of wallboard on the old ceiling. (FYI, it's a popcorn ceiling whether or not that makes a difference). Not attaching the joists to the old ceiling raises a question. Where/how do the new exterior wall leaves attach to the old ceiling to keep the sound from drifting into the remainder of the garage? I look forward to your response...time to go and deal with another hurricane. -Bill

Steve, Did you have any thoughts with regards as to how to step the ceiling? -Bill

Steve, Are you giving up on me? :cry: :wink: I think we can swing the slab...using a 3/4" form to contain it. So the floor layers from the top down would be: concrete slab, 3/4" inch plywood (from the form), 2x4"s turned on edge and resting on the 1/2" neoprene pucks. Please point me if possible towards any details concerning a stepped ceiling if there are posts out there that you are aware of, I've been unable to find something along these lines.

Sorry for the delay; no, I'm not giving up, just generally "buried" by life in general, extra 12-hour graveyard shifts, equipment failures, bad cold, etc... Before we can get into something as complex as a stepped ceiling, I need more info on your existing ceiling and framing - didn't see it in previous posts, without that you would need to build a "super header" across where the garage door track ends in order to support the stepped section. Have you checked with a straight edge to see how much ceiling height you would lose at the low end by just using straight joists and sloping the ceiling? If you built as my earlier drawing, you could use whatever access you wanted over the garage door, because you'd have a double leaf barrier already in place. If you can do an elevation and describe your ceiling/roof framing, I'll see what I can come up with... Steve

Steve, Here's what I'm able to make out WRT the ceiling. Going inside out it's 5/8" sheetrock attached to 1" wide furring strips which then attach to 2x4" joists. (I'm not really sure why the sheetrock doesn't attach directly to the 2x4s, but it is what it is. Then I have another 7" of blown-in loose-fill insulation lying on top of the sheetrock. Another thing, I have a steel? access panel into the crawl space near the center of garage. The height of the ceiling is 8'7" at the top of the garage. Three feet in from the garage door the height of the ceiling is 8'11" due to the slightly sloping floor. Using a straight edge that lines up underneath the garage door "hook," I have a vertical clearance of 85 3/4". There is enough clearance to be able to slope upward to the ceiling in the back of the garage at 8'11" from underneath the garage door hook. -Bill

OK, if your ceiling is attached to 2x4's can I assume they are part of trusses? Is this access panel into the attic crawlspace, or did you mean centered on a wall and accessing the area under the house floor? Will you need to keep this available? When you checked headroom, did you allow another 6-1/2" for a 2x6 new ceiling joist and two layers of drywall? Or is that 85 3/4" the TOP of your proposed ceiling joist? If the access panel is in your existing ceiling, and if those 2x4 joists are part of trusses, you could add a second layer of drywall to the existing and replace the panel with a heavier panel that sits on weatherstripped cleats - this would maintain your outer leaf of isolation. Then, you'd need to replicate that access into your new lower ceiling the same way, or you will lose either access or isolation. If you will be putting your mix position facing the garage door, the low ceiling won't be a problem. You would just maker sure your speakers woofers aren't centered height-wise, and the sloped ceiling would contribute to a RFZ for mixing... Steve

OK, the roof is gabled and the 2x4s are attached to trusses. The access panel is the one going up into the center of the garage ceiling which I want to keep available. Keep in mind that the access panel is located right next to the garage door opener. I would need a larger access panel in the lower ceiling to gain access to both the old access panel and the opener. 85 3/4" would be the top of the proposed ceiling joist.

If you will be putting your mix position facing the garage door, the low ceiling won't be a problem. You would just maker sure your speakers woofers aren't centered height-wise, and the sloped ceiling would contribute to a RFZ for mixing... Steve

OK, my original plan called for putting my monitors in the center of the room on the mixing desk with the monitors facing the garage door. Will this work with either a stepped/sloped ceiling?... Bill

Not too well - it's much better for stereo imaging if your ceilng rises to the rear as you face the speakers; otherwise, you get reflections from the ceiling back to the mix position. These will be out of phase in differing degrees at different frequencies; in other words, it will mess up the sound field. Does it look like you could replace that metal access door with something more massive, like a 2x4 frame with two layers of drywall on them? Your lower, new ceiling would also need this - then, getting access would mean lifting the lower "trap door" up out of the way, repeating that with the upper one, and climbing up through the hole. The good news is, 2x4 trusses are generally strong enough so you wouldn't have to worry about adding a second layer of drywall to that existing ceiling - since the lower ceiling wouldn't be trussed, you would need to use 2x6's for the lower ceiling joists. For two layers of 5/8 wallboard, these would span 10'8" using 24" centers, 13'0" using 16" centers, and 15'0" using 12" centers. You could stretch those distances by about 3 feet each if you don't exceed 2 layers of drywall, so probably 16" centers would work for you, they max out at 17'8" for 5 pound dead load - that's the weight of the frame AND all attachments per square foot, 5/8" drywall weighs about 2.3 lbs/sf and framing would weigh about 1.5 lbs/sf, so that would be stretching it a little. 16 foot span should be OK though... Steve

OK, so it sounds like I should re-orient the desk so that it is backed up against the wall at the bottom of the slope with the monitors facing into the room. Upon closer inspection the access door is a piece of plywood wrapped in sheet metal. The access opening is trimmed with an overhanging door molding. The door sits on the molding itself. The opening in the crawl space is framed between the 24" centers of the joists/trusses. The opening is about 30" x 21 3/4". So are you saying that the lower door would be lifted up and slid into the space between the new joist and the old ceiling? If so I guess that while the inner access panel is being moved I can also access the garage door opener...just want to make sure that I'm following you here.

For two layers of 5/8 wallboard, these would span 10'8" using 24" centers, 13'0" using 16" centers, and 15'0" using 12" centers.

Do you mean the length of the ceiling joists? If so (dumb question here) do 2"x6" boards come 16' long? OK, so if I go with two layers of 5/8" drywall for the lower ceiling, do I still need RC? Or is it not necessary because the lower ceiling is detached from the original ceiling? ... Bill

The lower access door can be temporarily stowed above the new ceiling and off to the side; without more headroom between ceilings it might be hard to tilt the panel enough to remove it entirely by first tilting it vertical and then rotating it diagonally so it would come out of the opening. Yes, that's what I meant about moving the mix position. IF the door opener is close enough to the ceiling access panel, you could get to both with the one (new) access panel. Yes, 2x6's come in up to 16' length, longer if you look around; and you're right, no RC needed since the two areas of drywall will be on separate frames. You would want the thickest fiberglass insulation you can afford for the space between old and new ceilings; use UN-faced though, since it's likely you already have a vapor barrier in the upper ceiling (you don't want TWO vapor barriers, just one closest to the cold side) Hope that helps... Steve