My (private) recording rooms, your suggestions please,...

Good evening everyone. Finaly it’s time, time to build my private music room and time to ask some ‘serious’ questions. I’ve been reading quite a few post over the last year or so and gathered a whealth of information, ..thank you all for that! Hoping not to break any rules I will try to explain my situation as briefly as I possibly can and then end with the first few questions. My situation: I would like to start building my recording space sometime next summer. The existing building in the drawing is part of an addition to our recently bought house. The addition itself has yet to be build, I do on the other hand, have a permit and a contractor who will do this for me next spring. The layout of the addition is more or less explained in the attached drawing. Some extra info: Outside walls will be 10 cm thick brick walls, weighing about 115 kg/m2 One of the 3 small windows (approx. 45 x 30 cm) should have the possibility to open. The glass in these windows will be one pane, thick (laminated) glass. How thick exactly, depends on your advice. The tilted ceiling of the outer shell will have extra strong/thick beams in order to hold two layers of 18mm OSB/Chipboard and if necesary additional layers of gypsum board (with Green Glue in between) attached from the inside. My goals: To have two good sounding rooms, so I can write and record my own ideas. This will be a private ‘studio’, just for me and some friends. My budget: I expect, after some research, to build (myself) the whole inner room construction for 2500-3000 Euro’s. Since I do not have a deadline, I could save up more, and finish later, if necessary. How loud am I? Pretty loud sometimes. This also is my main concern: adequately soundproofing the Tracking Room, so I can play some loud bassguitar or drums without disturbing my family or the neighbours. To give an indication: 105 dB (A-weighting) max. Mixing happens mostly at more moderate levels, every now and then turning it up just to check something. My ‘design’: Included is a sketchup file which will hopefully explain more than I can write. The walls of the inner room will be made of solid concrete blocks. (In our neighbourhood laying bricks is a more common way of building than with beams and gypsumboard, and I will feel a lot more comfortable having a heavy ceiling above me with thick concrete walls to hold it up. Apart from that: timber is not exactly cheap around here) In the design the bricks are drawn 10 cm thick although I’m leaning towards a somewhat thicker wall (14 cm, or 20 cm even?) just to be on the safe side. The doors will be bank-vault-style, similar like the ones Paul W. made (see his massive build diary in Studiotips) The inner ceiling will be 17x7 cm beams with a 30-40 cm spacing. Details of doors, floors and ceiling can be found in the sketchup-file. I would like to keep an average distance of 2 meters between the studio-part and the rest of the house (boilerroom, bathroom etc), for storage etc. The cavity of 50 cm between inner and outer leaf is meant for a few purposes: -Safety (the emergency exit) -Soundproofing -Airflow (opening one of the outside windows should allow a fresh airflow in between recordings, I have to walk through the cavity, hence the 50 cm) (an Airco system probably will be intergrated, but I haven’t thought that true yet) The concrete slab on which the inner rooms will be build, is isolated (20cm sand-filled ditch) from the rest of the building. This way I hope to avoid serious flanking problems. The slab surface is approx. 20 cm below ground level, this way I want to gain some ceiling height. (the basstraps and soffits(and drumkit;-) in my design are just drawn to give an indication of what I’m after) My questions: 1 - Do I create a problem with the two 78 degree angels on the back wall of the CR? Even if they will be filled with rockwool? 2 - Do I create a triple leaf with the double emergency exit doors and the outside wall? 3 - Is the double wall construction between CR and TR superfluous since I connected them at both ends, floor and ceiling? Would one thick wall be sufficient or would two connected walls still make a (small) difference soundproofing wise? (I did that because soundproofing between CR and TR is not my main concern, soundproofing between the ‘studio-part’ and the rest of the building is.) I also attached an alternative separating wall: a construction based on the ‘decoupling’ capacity of Green Glue. Would this be a better suggestion? 4 - How much Transmission Loss can be achieved? (This is my first concern, I would like to get as much soundproofing as possible without losing too much workspace, although I’d rather have an even smaller ‘studio’ which gives me no worries about annoying neighbours or family.) Regarding this: should I make my walls thicker? 10 cm walls are approx. 180 kg/m2 14 cm walls are approx. 220 kg/m2 Should I make the airgap between inner and outer room wider than the drawn 50 cm? (what is the point of diminishing returns in this?) I expect to be able to gain the same amount of TL with several layers of gypsumboard and Green Glue in the ceiling,....or am I wrong? 5 - The ceiling of both CR and TR are flat in my current design. I’m thinking about partially raising the ceiling of the TR (pink shoebox in the drawing) That way I could achieve up to 10% more volume. (and maybe even fill that raised part completely with rockwool and have a huge basstrap) Is this a waste of my time and money because it’s still not a big room (about 31m3 ~ 1100 cubic foot), or would this make a difference acoustic wise? For now,.. I’m going to leave it at this. It’s hardly what one would call brief, but I hope you will have the patience to read and react,.....(i’m sure I must have forgotten to mention something) Thanks in advance anyway! Regards, Phybeau BTW, I intend to post this in two forums, John Sayers’ and Studiotips. Not to start a competition or a should-out, just to gather as much information from as many different sources. I hope you’ll understand.

For some reason the drawing of the situation got left behind;-( Here it is: Greetings, Phybeau

Looks very interesting. Where is this going to happen?

Thanks Edo, hopefully it's still going to be even more interesting once it's finished. The location is the beautiful country side around Groningen. (Er gaat niets boven Groningen) I'm being a bit vague about the exact location, not that I have a lot of fancy instruments or equipment, or anything else worth steeling for that matter, but some people may feel different about that. And until I've got a proper burglar alarm installed I'm a bit reluctant to publish my address on the net. I hope you' ll understand!? :) Regards Phybeau

Do I ever... I fully understand that, no doubt about it. [dutch mode on] Vanzelfsprekend! --- speaks for itself --- [dutch mode off] Good luck on your project... figured out a name yet? Studio "Olde Grise" sounds pretty much Groningen to me :D

Hi Phybeau I suggest you take a look at the construction of Left Bank and Oasis studios at the construction site. http://johnlsayers.com/Studio/index.htm Both these studios are in a residential area with the adjacent houses a similar distance from the studio as yours will be. left Bank uses two 5/8" (16mm) layers of drywall - one for the outer, one for the inner - the air-space is 50mm!! The owner of the studio can record any time he likes - i.e at 4am if he wishes as the structure reduces the sound levels o aa poiint that you can't hear it from the outside even with a full blown bass and drums going full bore!! Oasis is the same - it has a block wall outer skin and a double layer of 5/8" drywall for the inner skin. Neither studio has a floating floor as such other than an inner timber floor mounted on 50mm x 50mm battens on rubber added for aesthetic purposes after the walls were erected, which sit directly on the concrete slab. In your case I would build the 100mm brick walls as per your drawing. I would then render one of the surfaces with a cement lining to totally seal the surface.I would then line the ceiling internally with a double layer of drywall. ( RC optional ). The inner walls would be a single 100m x 50mm stud wall frame with a double layer of 16mm drywall - again No RC involved. I would build right up the the brick wall with a 50mm airspace to the double brick supports in the brick wall making it a 150mm space from the main part of the brick wall. This should give you a 4m+ control room as opposed to the 3.6m you currently have. I would build an angled ceiling in both rooms lined again with 2 x 16mm drywall. For the floors I would build them AFTER the the iner walls have been built as per directions above. the money saved in all this process could then be spent on a proper aircon/heating system and some new toys ;) I hope this helps. cheers john

Thank you for looking into this! You brought me some good news and some bad news. Let me start with the bad news first: I have to seriously re-evaluate my initial design on account of the costs you mentioned. You mentioning NEW TOYS certainly did the trick! So I did some research: (I started to worry wether I made a miscalculation or maybe was misinformed earlier) So to find out, I’ve made a comparison for the walls only, since the ceiling, doors and windows would be be more or less the same in either construction. I came up with this: If I were to make a 50mm x100mm thick, timber frame, 30 cm spacing, I would need over 300 meter beams (according to my calculations 325 meters) for the walls only. (If I’d make the spacing 60 cm (which I wouldn’t) I would need only 220 meters.) I attached a small drawing to give an idea how I would go about this. One meter of new timber that size costs about 4 Euro/meter One meter of used timber that size is about 2 Euro/meter For now I’ve only found suppliers of 9mm (2,15 Euro/m2) or 12mm(4,90 Euro/m2) of gypsumboard. In order to get the 32 mm I ‘d have to have 3 layers of 12mm (€14,90/m2) Or, 4 layers of 9mm (€8,60/m2) My total costs for approx. 60 m2 of wall would be: New timber : 325 x 4 Euro = 1300 Euro Drywall: 60 x 8,60 Euro = 516 Euro A total of 1816 Euro I would go for the used timber option (provided I can find enough the right/same size, and go through the hassle of pulling the old nails out myself) then the cost would be 650 Euro less. On the other hand, I can get solid 10cm thick concrete blocks per 1000 for 850 Euro. (LxWxH=290x100x190 mm) I’m going to need 16,5 block per m2, so 1000 would be enough. In my comparison I didn’t calculate the screws, caulk/mud etc. And I left out the mortar/cement needed for laying bricks. On the other hand laying bricks would be a more difficult job than drywalling/framing. If I’ve made a mistake anywhere, don’t hesitate to say so please! The good news is, from what you wrote about your experience with the forementioned studios, and your work in general of course, it seems to me that my initial design (as far as soundproofing is concerned) is going to be good enough for my needs!? Even the ceiling? and even if I make the airgap (a little) smaller? (I’m stuck with a 20 cm gap at least, since the concrete floor has a 20 cm sandfilled ditch around it, for decoupling purposes) Or am I wrong in presuming that? One thing I forgot to mention in my first post (I apologize) is that I’m going to need a flat studio ceiling for storage. So it has to be strong, and flat. A sloped ceiling is out of the queston I’m afraid. On the other hand, for rooms this small**, I wonder wether sloping the ceiling would have a positive effect on the roommodes. (other than bending the direct reflections) (The flat ceiling is going to be properly treated on the inside of course.) **I’ve thought about making a single room studio, but I cannot come up with a good idea for large moveable, soundproof walls aka doors ;-) Those beautifull glass sliding doors, you so often use in your design, are VERY expensive around here. Something else you mentioned is a floating lightweight floor, and I’m not trying to be a smartass or question your knowledge! But is’n that going to be a problem for resonance frequencies? That is at least what I understand (mass-air-mass) It would be a solution, on the other hand, to reduce flanking between TR and CR. I hope you’ll find the time to respond, maybe even during the holiday season. But what better way to spend X-mas time than with the things one really cares about?(just kidding) Take your time though, I’ve learned to be a patient guy over the last few years,....with 3 little kids one has to! :D Have a good X-mas!, regards Phybeau

just a polite bump to bring it back on the first page,.. :wink: Regards, Phybeau