Hello All,
Firstly, a big thanks to everyone involved in providing so much helpful information in the one location.
I'm currently trying to design a small multi-purpose room (in one corner of my garage) to be used for tracking and also (by removing the instruments) can be used for final mixes. We are in a residential area (with so far fairly tolerant neighbours) and will be tracking loud drums/bass and guitar (mostly individually but also jams). Ideally the room should enable us to do individual tracking pretty late at night (up until around 9-10pm for drums).
After much time spent researching the possibilities I thought it a good idea to try to get some help.
There are a few limitations;
Unfortunately the garage must still remain a garage...
The remaining space is small... Location of the potential room and green areas in the posted SU pictures is/are free. A set of stairs runs from the red space up to the bedrooms/living room above the garage. The preposed room size in the SU pictures is approx 3.1m wide by 3.8m long (external).
There is a large steel support (universal) beam dividing the garage in half... To take this beam out of the equation means sloping any new ceilings under it- even less headroom...
Aside from the plaster garage ceiling there is also a floor above that which is supporting bedrooms (These are not in use when the room is)
The good news;
The walls of the garage are made of large concrete (besser) blocks (which are also filled with concrete).
In the preposed corner, the two concrete walls are buried about 1.3m deep in sand (white area surrounding garage in SU).
The floor is a solid concrete slab.
The current plaster ceiling is 2.64m high.
We really would like to make this work...
My main questions are;
If we use the two concrete walls as two sides of the outer leaf and build the other two walls (of the outer leaf) (with wood frames and plaster board) and then build the entire inner leaf with wood frames and plasterboard (4-6 inches inside the outer leaf), what is the best approach for the ceiling? At the moment I was thinking to remove the current plaster above the room and create a new ceiling connected only to the concrete walls and outer wood frame? Then construct a second ceiling that is connected only to the inner frame/leaf. Does this seem right?
Assuming this is the best way, what level of flanking would be present in the concrete block wall considering it has that much mass?
Otherwise would it be possible to use the existing plaster ceiling as part of the outer leaf if it is connected to the rest of the ceiling joists of the entire garage? What level of flanking would this produce when compared to the solution above?
How will the floor of the bedrooms above effect design? ie. will it create a third leaf if open to the entire span of the garage (approx 8.6m x 7.2m) ?
Does anyone have any other ideas/suggestions for this space/room?
I have also included a couple of photos to make things clearer (the High freq absorbers are there to help illustrate the dimensions).
Thanks very much.
Regards,
Rohan.
Demo den design in the corner of a semi-submerged garage?
Originally posted at johnlsayers.com, topic 17231.
Hi Rohan, and Welcome!!!! :)
Your basic plan looks fine, but the studio is a bit small (as you already know!): You are already inclining the front section of the ceiling (because of the steel beam), so have you also considered splaying the side walls a bit, and using up some of that green space down the side of the studio to gain a bit of volume inside? You could also extend the front of the studio a bit into the other green area, adjusting the angle of the ceiling as needed to fit. Room volume is critical for good acoustics: you want as much as you can possibly get. Normal recommendation for critical listening rooms is 42 m3. Obviously, you can't get there with your room, but anything you can do ti increase the volume is worthwhile. Have you considered "inside-out" construction?
Yes. No. Maybe. Not sure. Could be. Certainly. Never.... :) Those are the best answers that we can give you without knowing your numbers! By "numbers" I mean the two critical ones for starting the design of any studio: 1) "How loud are you?" 2) "How quiet do you need to be?" You need to put real decibel numbers on both of those. Saying "want to play drums at 9 PM" is not a number. Saying "so far fairly tolerant neighbours" is not a number. For the "how loud" number, get your self a sound level meter (beg, borrow, or buy: they are not expensive), and measure a real, live worst-case scenario in your garage as it is right now. Get your biggest, baddest, loudest bunch of musicians that you can find to bring their best, nastiest instruments, supply abundant "refreshments" for them, and tell them to jam their absolute hardest, with the intention of bringing the walls down. While the are doing that, measure the real levels on your meter (C weighting, slow response), both inside the room, and also outside it: in the rest of the house, around the garden, and at your property line. That gives you an answer to the "how loud are you" question. After they all go home, at 3:00 am take some more readings in the exact same places, to find out what the typical ambient levels are. And one final step: cal your local municipality and get a copy of the noise ordinance, to find out what the legal limits are. Those two steps will answer the second question: "how quiet do you need to be?". Subtract "B" from "A". That is your number. It tells you how much isolation you need in order to stay legal and keep the neighbors consistently "fairly tolerant". Based on that number you can study the literature to see what types of construction will give you that level of isolation within your budget. And that brings up another point: What is your budget? You didn't mention it, but it isn't enough! :) First rule of studio building: "No matter what figure you have in mind for your budget, it isn't enough." Multiply by an random number you can think of, add a zero on the end, and you are approaching the real amount needed! :!: Seriously, budget is important. With all of the above info, we can give you more intelligent suggestions on how to build your studio.If we use the two concrete walls as two sides of the outer leaf and build the other two walls (of the outer leaf) (with wood frames and plaster board) and then build the entire inner leaf with wood frames and plasterboard (4-6 inches inside the outer leaf), what is the best approach for the ceiling? At the moment I was thinking to remove the current plaster above the room and create a new ceiling connected only to the concrete walls and outer wood frame? Then construct a second ceiling that is connected only to the inner frame/leaf. Does this seem right? Assuming this is the best way, what level of flanking would be present in the concrete block wall considering it has that much mass?
Mass doesn't stop flanking. In fact, it helps it! as a general rule, dense materials normally conduct sound better/faster than less dense materials. So the idea is to stop the flanking at the source. So if you are concerned about flanking, still decouple the ceiling if possible, even if it has to be attached to the concrete walls as a third leaf. Also, build a drum riser and use isolation pads under amps and cabs to keep direct impact out of the floor. If you suspect flanking will be an issue, than try to keep sound from ever getting into the structure.Assuming this is the best way, what level of flanking would be present in the concrete block wall considering it has that much mass?
Yes, it will be a third leaf, but that's not the end of the world: there are ways of dealing with that, if it turns out that you have no choice. That said, the way it looks right now, I think you might need to take out that existing ceiling: it is most likely just thin drywall (probably only 1/2" or even less: not much use for isolation), and you don't even know if there is any insulation above it, how well the floor above is sealed (critical!), or what surprises might be lurking between the joists.... But anyway, your first action should be to get out your sound level meter and your cheque book, put some real numbers on your build, both in terms of decibels and in terms of dollars... - Stuart -How will the floor of the bedrooms above effect design? ie. will it create a third leaf if open to the entire span of the garage (approx 8.6m x 7.2m) ?