slab or floating floor?

Steve, in your reference sticky section you have a link to How wall/floor details affect sound insulation http://irc.nrc-cnrc.gc.ca/newsletter/v7 ... ion_e.html It says: "It should be noted, however, that the optimal physical properties of the topping system for airborne sound are different than those for impact sound. Although attenuation for both types of sound is improved by adding a topping that increases the mass of the subfloor, the hardness of the surface exposed to impacts should not be increased. Toppings such as gypsum concrete should be used in conjunction with pliable materials placed either on the surface (such as carpet or vinyl) or between the topping and the subfloor (resilient interlayer)." since i am planning to use a sandwich of 5/8 ply, 1/2 gyp, and 3/8 ply, do i need any more pliable materials placed on the surface of the gypsum, or should i not worry about this statement b/c i don't have anything under the studio except dirt?

Jeff, I doubt you'll have ANY problems due to IMPACT noise for reasons you already stated - however, I would NOT recommend ANY layers on a floor that are only 3/8" thick, other than a possible MLV or similar layer which is NOT the final course - for any floated floor, high mass is needed in order to keep resonance low, and also 3/8 ply won't span any normal joist spacing, so shouldn't be used as a layer either. Mainly though, the mass is the main thing - for this reason, I would stay with 5/8 or thicker materials (the 1/2" gypsum inner layer is OK though) Steve

damn... i already got the stuff delivered, what can i do? just replace the 3/8 with 5/8? the 3/8 was to serve as the top layer. is there any use for 3/8 plywood, or am i fu(#@&d? also, what is MLV? i made the diagrams of where the screws should go and i'm about to apply the R19 and poly vapor barrier. then the 5/8 goes down, and caulk. (btw, i got about $2.29 per 29 oz. tube of acoustic caulk plus free delivery from grabberman, bought a case - i think that's a great price!)

3/8 ply won't span any normal joist spacing, so shouldn't be used as a layer either

i have 16" centers, even as the 3rd layer it's no good?

whew! glad to be back online and what a relief! regarding the back of the control room... it is supposed to be absorbent from what i gather so here is my plan for the back wall of the control room: - outside world (evil) - aluminum house siding - plywood on outside of house - r-19 - control room wall studs - RC - 2 layers of 5/8 gypsum - 4in roxul - cloth - inside (womb) does this sound ok? should the r-19 be faced or unfaced? thanks!

Does the back wall already have house wrap (like Tyvek) on the outside? Where you're putting the R19, it should be UN-faced. The entire wall system should have only one vapor and one air barrier; the tyvek outer for air barrier, which will allow things to dry, and the inner VAPOR barrier (like the 6 mil poly) which should be right underneath your inner gypsum, between it and the studs. If you're using double frames like that, I see no reason to hassle with RC - it will probably HURT your performance a bit, but definitely won't help. RC is for ceilings where you can't use separate framing members, and walls with single frames that don't allow any decoupling. If you can spare the floor space, I would put the inner roxul in a separate frame at least a foot inside the inner gypsum, and fill between it and the gypsum with unfaced pink batts; you'll get a more even bass response at the rear of the room, and just generally a smoother sounding room... Steve

I'm not sure if there is tyvek or not... and i'll have to see if i have a foot to give. will i need the vapor barrier on the ceiling too? what about the "vapor barrier" that is built into the facing of the batts?

Jeff, check out the new post on More Vapor, Moisture links, found in the REFERENCE section at top of the forum; if you're thoroughly confused after that, I'll see what I can do (kinda rushed ATM)... Steve

Hello! I'm back, with some progress on the studio. This is going much slower than I had originally planned, but I'd rather do it right the first time than realize I made mistakes due to haste. With that said, I think it's going great considering I'm building this monolith with my own 2 hands inbetween day job hours. anyway, I have a question about my garage door. It is a thin, uninsulated metal door that I need to wall in. Steve, you gave this advice in a previous post:

One possible (even heavier ) way to get around this - glue as thick (and as large) sections of sheet rock onto the inside of each thin panel in the door as you can get, without them sticking up further than the heavier rails and stiles of the door - then, finish out LEVEL with joint compound, working with each individual door segment (hardware removed) - once the inside surface is level, caulk the inside of each panel smooth and attach to the wallboard/frame as you did, and call that entire assembly your outer leaf.

My question is, can I leave the garage door on it's rails with this solution, or will it be too heavy to stand? thanks! :D

"thin, uninsulated metal door" - for that scenario, I'd read through this thread - http://forum.studiotips.com/viewtopic.php?p=3589 BTW, I hadn't considered the weight and being able to stand up; such panel type doors seem to do OK when hung horizontally from the door tracks when left in the OPEN position, and it's the same tracks holding the door when it's vertical (less gravity trying to buckle the door) - still, with a panel type door doing my suggestion, it wouldn't hurt to add some stud framing to the door on the inside, AFTER the leveling process between panels and BEFORE building the INNER leaf. However, that suggestion you mentioned was intended for a "stile and rail" type garage door, NOT a metal one; for that, you'd be far ahead with the above link, paying particular attention to the comments of Eric and Rod IMO... Steve

Thanks for that link, Steve, it was fantastic and a great read. The main difference here is that my garage door will serve as the outer leaf of my double-leaf system. Therefore, I'm thinking I should find a way to build mass and/or lower the resonant frequency of the door. I think now i understand that I can keep the garage door on its rails and possibly use the aluminum damping materials (referenced in that thread) to lower the door's resonance. Then seal it up with caulk and insulate it. What do you think of this solution? thanks!

Sounds like the outer leaf would be pretty marginal; but if you keep the air space as deep as possible, fill with insulation, and use at least 3 layers of gypsum for the inner leaf, you may be OK; if you can give more particulars on the type/thickness of metal, and how much air gap you can afford to leave between it and the inner leaf, I'll hazard a "SWAG" on what to expect... Steve

ok, the door is a Raynor Decade - no windows, no insulation. only the raised panels. It seems like their stock item from 20 years ago. on this web page, it shows the specs as "2" thick with 24-guage steel skins" http://www.dasma.com/PDF/Publications/P ... 0Panel.pdf As for the air gap, it's going to be 4" from door to floor 2"x6" wall sill 3 x 5/8" gypsum So the air gap will be just under a foot. when you say "fill with insulation" does that mean A) overstuffing 12" of insulation similar to how the floor was insulated or B) attaching insulation to both leaves separately and leaving an air gap between the leaves? Please let me know the possibilities here as that is a lot of insulation in option A! thanks again! God bless You and the Internet! :lol:

OK, before we get into this much further I need to know your intentions as to the future of this garage door; will you at some point in future want to return the door to standard openable condition, or is this to be a permanent change? Also, if that is a "steel skinned" door, does that mean that each hinged section of the door is one piece stamped steel, with some kind of "filler" inside? If so, what's the filler? How heavy is it? And, if those are stamped steel panels I don't think the sheet rock and mud approach is a good plan; don't remember reading anywhere that sheet rock joint compound sticks to steel really well... Steve

steve, at some point i may want to sell the house, so as little destruction as possible is best. i would actually like to keep the door on it's tracks b/c i think that is the safest bet for my limited construction ability. that said, the door itself will most likely be rendered inoperable forever by sealing it up w. caulk anyway. not sure what you mean by filler, i don't think there is any. it's just a standard metal garage door. i'll try to get close up pics later tonight. how would i determine the weight?

I'm gonna wait for the pix; but I don't think caulking (with the right caulk) will be irreversible. Your pix should include a close-up of one of the gaps between hinged sections of the door, first with the door DOWN and then with one of those gaps opened up just at the top of the door opening... Steve

I hope this works... here is a shot of my garage door http://brooksound.com/studiopics/garage ... aps019.jpg closer... http://brooksound.com/studiopics/garage ... aps008.jpg SUPER CLOSE UP http://brooksound.com/studiopics/garage ... aps013.jpg here's the bottom of the door... note the 4" gap between the actual door and the end of the door rail. http://brooksound.com/studiopics/garage ... aps012.jpg my thoughts are to build the floor up to the door rail and build the interior wall on top of the floated floor. with a 2x6 sill, there would be about a 10" minimum gap airspace between where my garage door (outer leaf) ends and the gypsum (inner leaf) begins. here's a shot of the garage with the door up. see how far the rail protrudes into the garage. by building the interior wall infront of this rail i will gain airspace between the 2 leaves. http://brooksound.com/studiopics/garage ... aps016.jpg now how can i get the best soundproofing from that garage door in the most cost efficient and construction friendly way? please tell me what you think here, thanks!!! :lol:

When the door is down, how tight are the gaps between individual, hinged panels of the door? Also, gap size around the perimeter of the door? What I'm thinking is, use stick-on weather strip between each panel of the door, lowering the door a panel at a time and inserting the weatherstrip into the cracks while they're open at the curve of the door track; then, once the door's shut, fasten from the inside with some long screws into the side frames, and across the top of the door if possible, then caulk in place. Remove the parts of the door track that protrude further into the room, so you don't have to work around them for the ceiling (unless it won't be in the way) - then, as you panel the inner frame, fill the gap between the door and the first wall panel ENTIRELY with blown cellulose insulation - this will damp the door panel, provide your heat AND sound insulation, and also damp the inside wall panel. Cellulose has been tested and found to meet or exceed sound performance of just about anything out there. Because the outer door is relatively light, 3 layers of 5/8 wallboard on the inner frame will be necessary. The extra depth of air gap/insulation will help negate the lighter outer leaf of the barrier. Total hermetic seals EVERYWHERE of course... Steve

the gaps are not very big at all. that's great advice, thanks! one question, what do you think of the damping paint or adhesive? http://www.mcmaster.com/ search for item: 9709T19 thanks!

Couldn't hurt; although that was part of the reason for the blown in cellulose instead of other insulation. Both would be even better... Steve

things are going great and we are sealing in the garage door nicely! thank you!! :lol: i'd like to build the interior walls and ceiling with steel studs, but i've never worked with steel, only wood. can you point me to some guidelines or a how-to guide on steel framing? thanks again!!! :lol:

As humid as the whole east coast is, I would tend to stay away from steel framing and possibly even gypsum in some cases - I recently read a report from one of the Canadian building sites (IIRC) about water retention in different construction; the level of water retention allowed before damage occurred, using a 2000 sf house, was 5 gallons total for gypsum/steel framing, 50 gallons for wood frame/wood paneling, and 500 gallons for all masonry construction. Steel studs transmit heat better, so get colder in winter which causes more condensation; this collects in insulation, and causes the studs to corrode. Check out these pages for more - http://www.maconline.org/designalert.PDF http://www.buildingscience.com/resource ... efault.htm HTH... Steve

Hey Jeff! It's been a while since we've heard from you. What's the status of your project?

jeffjazz wrote:

Thanks for that link, Steve, it was fantastic and a great read. The main difference here is that my garage door will serve as the outer leaf of my double-leaf system. Therefore, I'm thinking I should find a way to build mass and/or lower the resonant frequency of the door. ....!

There's no difference in this regard. My doors and wall were serving as the outer leaf also. :) Paul

man, it has been a while, but rome wasn't built in a day! we now have the framing up for the tracking room as well, and that has a gabled ceiling. one wall is 8.5' high, the other wall is 12.5' high. for the ceiling, i am going to put bass hangars of mdf and insulation in the angled "roof" part, and use a drop ceiling grid at 8' to hold a false ceiling of insulation. then i shall cover it with thin plastic and cloth. how does that sound? what is the recommended way to hang the bass traps from the rafters? many thanks! don't have a digital camera anymore, but am working on the pics.

Jeff, Great post. I am building something similar right now next to my garage. My question is this. My garage right now serves as my control room and behing it I'm laying a concrete slab that will measure approximately 18' x 16'. I'm wondering if you guys think it's necessary to build a raised subfloor or just leave it concrete. I am leaning more towards raising it, since this will mainly be a drum tracking room. Let me know your thoughts. I'm doing resiliant channel walls but needed to know if it's necessary to build double walls with spacing in between each one? I want to be sure that I don't disturb the neighbors, but it would be nice to save the money at the same time. Let me know your thoughts... Thanks!