Modular room-within-a-room panels?

As a professional voice-over performer, I need a home studio. I also play acoustic guitar, very non-professionally, and would rather not be heard by my neighbors (although they obviously don't give a hoot about the reverse). But my apartment is a rental, so building a permanent room within a room is not an option. Also, it's on an upper floor of a midrise that appears to be timber construction (circa 1960), so weight is an issue, too. (My file cabinets, couch and what-have-you don't seem to have caused a problem, but I wouldn't want to put a ton all on one point.) My office is moderately sized and angular, very well suited to voice over recording, with plenty of room to swing a guitar. And until recently, the apartment downstairs has been empty, and my upstairs neighbors were very quiet or not often at home, and at times the apartment was empty. That all changed recently. The new upstairs neighbors are loud, don't remove their shoes, may not be fully carpeted, are a couple so there are the usual conversations. I can easily hear their voices, not the actual words, but maybe that's because they're in a foreign language... but a former tenant upstairs, I could hear her sneeze! These folks don't shout, but do talk loud enough that I hear an echo effect (not sure if that's sound going out the window and bouncing off a nearby building, or what). They must have a Wii game or something because I often hear gaming music and SFX and LOTS of bouncing at all hours. They also have a washing machine or something (it's not near any water hookup), which from time to time, for up to an hour, makes "whooshing" sounds (sort of like a floor polisher) and a regular VLF thump that I can feel in my body (about one thump per second). Oh, and occasionally one of them honks on a saxophone, for up to half an hour, just making noise, absolutely no suggestion of having had a lesson or practicing or even knowing the scales. Just honks, bleats and squeals. I'd complain to the landlord, but you know what they say about people who live in glass houses. Acoustically, the walls are transparent both ways, and I sing along with the radio, do vocal exercises, have my own stereo, etc., and I don't want to invite counter complaints. And unfortunately, for now, my moving is not an option. I realize I'm not going to be able to deal with the thumping machine and the bassy footfalls, but I would like to block their normal conversation, and my own performances, vocal exercises and my guitar. The point is to increase the periods of time when I can record. (Unfortunately, apparently the couple also doesn't work regular hours.) I've shopped modular sound booths. My budget is roughly $1,000, so I'd have to build my own. But I don't want to chop up my nice office by putting a 4x4 box in it. It's very comfortable, I've sound-conditioned it, and things were going fine until the jerk upstairs moved in. So I'm hoping I can build a "modular room-within-a-room," similar to an isolation booth, but room-sized in dimensions, and with the panels being of manageable size, say each being 16" or 24" wide. See sketches and photo below. The main reason for making the panels relatively small is to resemble a stud wall, because they will support a large ceiling. Also if it's not working as hoped, I can reconfigure things if the panels are not overly large. And, when I do eventually move, I can take them with me, to re-use. I showed these "plans" to the folks at QuietRock, and they can't assure it will solve my problem. But they didn't say why it wouldn't work, or even that it won't... just that they don't endorse the idea. Posts in the forums here seem to say that QuietRock and such won't be that big a help anyway, that 5/8" gypsum or MDF might work just as well. My biggest concern is tightness and air gaps, but I feel able to handle those factors. Using the panels to float a false ceiling above me is another concern -- it's a 12-foot span -- so before proceeding I'll have to review that structurally more carefully than I have so far.. I've read the stickie post on raised floors, and so for now am not planning to beef up the floor, except for sound control (padding and carpet). One function of a raised floor would be to keep the bottom of the "wall" from catastrophically sliding in, but there will be heavy cabinets etc at the base of the panels, and I can secure a horizontal stud along the base if necessary. BTW, this will continue to be my office. It's ideal having everything accessible while at the mic (including phone, computer, etc.). The computer CPU is in another room, I have carpet on the walls, and I slide heavy drapes over the other hard surfaces when recording. It works well enough for voice over. Preliminary thoughts on this? How much isolation can I realistically hope to achieve? Again, I'm not the one playing the sax, don't have a drum set, and my voice work is usually very quiet, but a occasionally a script might call for some shouting. I'll just have to avoid recording during the thumping machine and Wii, and maybe I can talk with them about removing their shoes (I can't afford to carpet their apartment), if I don't in turn annoy them. I just need the level of isolation that a better-built building would afford, and larger periods of opportunity vs. my neighbors. (If someone moves in downstairs, I'll have to think about the floor, but am keeping my fingers crossed.)

why not make the panels 24" wide - 1/2" OSB + 2x 5/8" drywall - inside-out. then cloth and slats on alternating panels. were you planning on putting a ceiling on them? floating - use damped membrane floor with foam or rubber under the walls to decouple.

Hi Sensible, It's a very cool idea, (and one that I myself have been entertaining for some time as well) but let me share some cautionary thoughts. Structural Issues:If the panels are to support a false ceiling, they have to be very strong. Like wise the ceiling portion would have to be capable of supporting its weight over the span you indicate. Web search for Load Span Tables to see what I'm talking about. If the panels will be used as gobos only (free standing and not supporting a ceiling), then it would be easier, but no matter what - the materials used should be fire reisistant or retardant. Fire Issues:If a fire did break out in your room it would be very difficult to escape the flames if your assembly was on fire itself. In fact, one problem with this idea is the issue of fire blocking in general. See fire blocking threads on this forum. If sprinkler systems exist in your unit then it's a no go. You'd probably have to install a smoke alarm under the false celing. Celing height inside your inner room might also have to be considered here - if it was less than 8' tall I wouldn't go for it - too much risk of asfixiation due to smoke, as well as other issues. Sealing & Ventilation Issues: Sealing it up air tight might also be an issue - air tightness would require a sealed door assembly, or two if the issue of fire escape wasn't thought out very carefully - a reliable sealing door is difficult to produce even if there aren't removable walls to contend with. Ventilation of some sort would be required. See HVAC threads this forum. Electrical Issues: In order for this to work to any degree as a usable space, you'd have to supply electrical to the inside of the room. You could assemble this by using SJC or other suitably sized extension cable to a box mounted in your panel, and plug this into your existing wall outlets, but I'd consult with an electrician to verify that have an exterior-rated extension cable could be used inside a wall assembly without overheating. Sound Isolation Issues: I'd be willing to bet for normally portable weights that wouldn't cause damage to the structure of the building, you wouldn't get much sound isolation. There are many issues here- decoupling of structure, triple leaf conditions, damping of the cavities, etc. Not to discourage you - have you looked into either modular isolation booths that are commercially produced, or temporary (such as tradeshow booth) structures to see what features they might have that could give you ideas? Bill