Converting Garage to Auralex Acoustics 101 Control Room

Back on page 2, John posted a pic of Oasis after the truss replacement. That the same kind of roofline that I'll end up with.

I guess I will have to wait for pictures then.

Ok , yeah, the truss replacement part of it should go pretty quickly. Once we have that finished I'll post pics so we know exactly what's going on with the roof. At that point we can figure out the best position for the control room. Not sure when my contractor is free to begin, but I'll keep you all updated when we make some progress.

"He explained to me how it can be done" That is what I want to know. You have an existing truss roof per your thread pictures. Any modification to theses trusses alters the math that went into designing them and they will no longer perform as specified under the loads calculated for them. In effect, your contract is null and void and your insurance doesn't cover. Are you guys talking about a complete roof removal and restoration? And if so why are scissor trusses not part of this because now it can be done. With the proper approval, paperwork, etc. etc. Curious still, Brien

Thanks for the heads up. He's talking about cutting the trusses and modifying them in some way (I would explain it I could remember it accurately, but really I can't). If modifying a trusses is a big NO-NO, I can just go back to 8' ceilings.

Just sent a request to my builder to get his proposal in writing. Will keep y'all posted.

While I'm waiting for him to respond, another thought occurred to me. There might be a middle ground that would work for my particular situation. As I understand it, the main disadvantage of having low ceilings is that acoustically it's going to create more problems than a room with high ceilings. As I was thinking about this, it occurred to me that maybe I'm putting too much emphasis on the sound*proofing* aspect of this project. In reality the sound *of the control room itself* is much, much more important for my situation. The main thing that I'll be doing in this room is editing and mixing. I mix at moderate volume... you could talk over the mix and still and be heard. I will also be playing some electric guitar in there, but again, even with that, I practice at very low volumes through a combo amp. So the sounds generated inside the mix room are never going to be particularly loud. The only time it gets loud is when I bump the mix up for a few seconds to check something at higher volumes. I never leave it up though, it comes right back down again. My closest neighbor is far enough away that even in an unfinished garage, moderate sounds like that aren't a problem. So I'm thinking... why not just leave the trusses in place. Build the control room walls as we've already worked out in John's design, but don't actually add a control room ceiling at all. Instead just insulate between the truss/rafters, and stretch some fabric over it; this fabric would appear (visually) to be the control room "ceiling". But in reality the sound would cut right through it and travel all the way up to the existing garage roof. That should give me the sonic benefits of a high ceiling, no? I realize this approach wouldn't do anything in terms of isolation, but where I live... isolation is more of a luxury, not a necessity. Also consider the cost of doing it this way vs. a full truss replacement... I guess with this approach, my air exchange room would need to be fully enclosed (but maybe with just a drywall ceiling attached to the trusses), so that the mini-split "whoosh" wouldn't make it into the control room. But overall this seems like a much simpler idea that would still leave me with the best possible sounding mix room. Thoughts?

Still exploring this alternative. To re-cap the situation: 1. We can't do a full truss replacement. 2. We're trying to avoid the sound of an 8' CR ceiling. 3. If some sound makes it from the CR to the outside world, it's OK since neighbors aren't very close by. 4. We do, however, want to block rain noise on the roof from getting into the CR We're considering something like the following, from top to bottom: * The pink area in the 3.5 inch space is insulation. Fluffy, or rigid? Or maybe foam, which would harden up and eliminate that air gap (essentially beefing up the ceiling) * Drywall (1 or 2 layers) will be hung from the trusses as shown (on RC-2 strips?). * The black sheet attached to the bottom of the trusses is stretch fabric, which is all you'd see from within the CR. * The remaining opening space between the trusses will get insulated as well, just for heating purposes. (Winters here get subzero quite often)

Hottmeal wrote:

He's talking about cutting the trusses and modifying them in some way.

:shock:

Not to worry, that idea isn't happenin'. We are leaving the trusses in place.

Looks like the above diagram will be: pink/fluffy insulation in the gaps, RC-2, then drywall

Quick question/clarification about insulation type. I assume that we want to preserve the air space (i.e. fluffy insulation) between the existing garage ceiling and the new inner ceiling that will be on the RC-2 (or iso clips). This would give us mass (existing garage ceiling), then 3.5 inches of air, then mass (inner ceiling). But we're wondering if anyone can comment on the effects of adding "rigid" insulation instead, like hardening foam or maybe even blueboard? Being in an area that gets extremely cold in the winter, we're kind of shooting for the highest R-value possible.

Hottmeal wrote:

But we're wondering if anyone can comment on the effects of adding "rigid" insulation instead, like hardening foam or maybe even blueboard? Being in an area that gets extremely cold in the winter, we're kind of shooting for the highest R-value possible.

The rigd insulation you are describing has minimal acoustic effect. You can get comparable R-values in batt type insulation. Andre

Thank you very much! I also take this to mean that having the air space in there (batt insulation) would be preferable to filling it up with something solid. Correct?

For isolation, yes. The way I see it, anything solid introduces two possible risks: You could create a flanking path if it is too dense, and you could interfere with the MSM properties. Not saying you would, but there is a possibility. You won't know unless you try it, and if you do try it, ... well then you just became your very own independent acoustical test facility! :) You'll be breaking brand new ground in acoustic theory! Better to go with tried and tested solutions, if you ask me. You might be fine with what you suggest, but you also might not. IMHO - Stuart -

Hottmeal wrote:

* The pink area in the 3.5 inch space is insulation. Fluffy, or rigid? Or maybe foam, which would harden up and eliminate that air gap (essentially beefing up the ceiling) * Drywall (1 or 2 layers) will be hung from the trusses as shown (on RC-2 strips?). * The black sheet attached to the bottom of the trusses is stretch fabric, which is all you'd see from within the CR. * The remaining opening space between the trusses will get insulated as well, just for heating purposes. (Winters here get subzero quite often)

I am still trying to get my head around this. You say that you are going to insulate the rafter part of the truss. Is that correct? And when you say "Drywall (1 or 2 layers) will be hung from the trusses as shown" there is not any description of what this means either. The above statement wouldn't matter much except, then you said, "The black sheet attached to the bottom of the trusses is stretch fabric" This reads like you are wanting to insulate the rafter part of the truss, install RC to the bottom of the rafter, install the mass to this RC and then install a fabric over the joist part of the truss. Help me out here :)

xSpace: Let me summarize the situation and clarify the idea that we are experimenting with. As you know, my truss system is here to stay. I can't replace it, and I won't modify it, so I need to work with it. The bottom of the trusses are 8' off the ground. So with standard practices, my height will be limited, regardless of whether my control room ceiling is independently framed (below the trusses, resting on the control new room walls) or attached to the bottom of the trusses with RC-2. Sonically I am still stuck with a ceiling that is somewhere around 8' in height. If it comes to it, I can definitely build a room in that manner, but I'm trying to explore alternatives first. So I'm thinking outside the box for a minute. Would it be possible to somehow build my control room ceiling *higher* than the trusses, to make the control room *sound* like a bigger space? In other words, can I get the same sonic benefits of a vaulted ceiling without actually having to build one? Looking at that sketchup diagram of my truss system, the proposed drywall location follows the slope of my existing garage ceiling and peaks at about 13'. That drywall would be used as my control room ceiling. Control room walls would then *somehow* be built to extend up into that space until they make contact with that drywall layer. This would result in an unusual design where the bottom of the trusses would actually be penetrating through the drywall of the control room walls at certain points. (I could caulk around such joints, but still, the penetration would be present). The black fabric just forms a "fake" ceiling so that when you're standing in the control room, and you look up, you wouldn't have to see any of this :) One obvious downside is that many flanking paths would be introduced wherever a truss penetrates a control room wall. I don't know the extent to which that would affect the sound"proofing" aspect of the build. Maybe it would only damage it slightly, or maybe it would destroy it completely. But the room (should?) still sound like it has the high/valuted ceiling when you're inside it. In terms of soundproofing requirements, keep in mind that I live in the woods on the side of a mountain. My closest neighbors are far enough away that I could even mix in an *unfinished* garage and they wouldn't be bothered. (I've actually tried this as a test... I set up some monitors in the garage, ran a mix through them, went outside, and started walking. By the time I got to the neighbors house I couldn't hear it at all). This doesn't mean that my soundproofing requirements are zero, however, since I do need to block sounds from getting into the control room. Rain hitting the roof, wind blowing outside, and AC fan noise from my minisplit are all things I'd rather not hear when creating a mix. I think that summarizes it all. Again, at this point, we're still just brainstorming an experimental idea. If we scrap it and decide to go with a standard build, I do own Rod's book and can definitely walk my contractor through chapter 4.

Since all options are on the table, I did have another chat with my builder about his original truss replacement idea, the one xSpace was asking for more details about. Basically what he was talking about was removing the trusses and replacing them with a system of 2x12's, in a "conventional rafter" or "conventional roof" system. He reminded me that not all buildings use pre-fab trusses, and that this is standard practice on many homes and garages. He can give me a list of dozens of examples of this in the town that I live in, many of which he built himself. He is fully confident in such systems and I have little reason to doubt his construction expertise. So that option is back as a strong candidate for this project. (I can't explain in detail how all the 2x12's connect and such; I assume that the term "convention roof system" says enough)

I wonder why you decided to leave the trusses in place?...

Ignore the lousy spammer....

Quick update for you all. We've considered all the options and have decided to entirely replace the trusses with a "conventional rafter" system. This will leave us maximum headroom under which we can frame in the control and air exchange rooms. We'll be able to use standard studio build techniques (nothing experimental). As you may remember from my initial pics, I have a large triangle shaped vent in the peak of the ceiling, plus long vents running the length of the garage where the roof overhangs. Back on page 2 John indicated that I'll have to seal those off: "well you are going to have to seal that off - unfortunately a soundproof studio is an airtight studio." To that my contractor has asked the following question. I told him I'd check with the experts here to find out. "How do you propose to properly vent the roof system if the soffit vents and gable end vents will be sealed off? Understandably, this needs to be done for soundproofing, but what about building code and the ability of the roof to breath and properly vent itself? The shingle manufacturers will not warranty shingles if a roof is not properly vented, and the roof sheathing will have moisture/mold issues. Another concern will be ice buildup in the winter season. One of the concepts behind roof venting is to keep a cold space above the insulation to allow the moisture to escape and to allow the snow sitting on the roof to remain as snow and not be melted. If you close off these vents then how does the roof breathe? Obviously if you are closing off these vents than you must be using another technique to vent the roof. How is this done?"

that's why I recommended scissor trusses. You line the bottom of the truss to the outer wall which allows for the vents in the eaves to vent the cavity above the lining as required.

Ahh, so those vents along the side aren't actually blocked up. They are just out of sight, behind a layer. He can do a similar thing with conventional rafters (I remember him mentioning it before)... we were just confused at the thought of actually removing/blocking up those side vents. Thanks for clarifying!

Photo update. After considering the options, I decided to spend this year's budget raising the ceiling. It puts studio completion off by a year, but the end result will be soooo much more comfortable to work in. To anyone reading this: This part of the project is most definitely *not* DIY. I hired a commercial build crew for this, and let their construction expertise lead the way. This part involves entirely replacing the truss system with a "conventional rafter" system. My particular crew has decades of experience doing this. If you are faced with the same situation and want to try this approach, be sure to get all the proper sign-off from your structural engineer, your town, and your insurance company. Taking delivery of the 2x12's. These will form the supports for my roof. The basic idea is to repalce the trusses by sistering these 2x12's alongside the original 2x4's. The new rafter system is nailed into place first and then secured in the middle with collar ties. When everything is in place, the old trusses are then simply cut away and discarded. The following picture shows the new system in place. You can see where the old 2x4's have been cut away. Also note how much more massive the new supports are. Installing proper vent: Old trusses gone. Garage door hardware gone. Old garage doors gone. We decided to wall off the garage door openings entirely, then dress the outside of it with "barn board" siding, to make it appear that it's a garage with custom wooden doors. More on that later. Insulating for weather: (We did not spraypaint the insulation black... it came like that in the package for some reason) Hanging drywall. Flanking noise through the ceiling itself isn't a concern for me given where this build is. So we attached the drywall directly to the 2x12's. We did not use iso clips. Garage "doors" (in reality, a solid wall!) Needs staining. So now the project's at a standstill because my budget is spent. It will most likely resume next spring, or possibly this summer if I can sell some things to raise some cash. I ran some initial sound tests just to give everything a reality check. (Keep in mind that the control room is not even built yet, and there is only a single drywall layer mounted directly to the 2x12's of the roof.) Normal mix levels do not present a problem for anyone. You can barely hear the music when standing outside the garage. With the monitors cranked to extremely loud volume (louder than I would ever mix at) you can hear the lows inside my own house, but the sound does not reach my closest neighbor. In the end we'll have two drywall layers all around, with green glue in between. I have the framing materials for the control room walls, but that part of it won't begin until I can raise more money. Looking at the big picture, the *feel* of the room is really huge now. The pics don't quite do it justice. It is 24'x24', and the ceiling is about 12' at its highest point in the center. In terms of comfort, it's a night and day difference between this and an 8' ceiling.