slab or floating floor?

- when should the tyvek be applied, or do i really need it? You need a vapor barrier just behind the closest paneling to living space, so it would go on the joists just before the first layer of OSB. Don't remember if your slab is well-drained (dry) but if not, this needs to be discussed as well. - do i need to use construction adhesive for the first layer of 5/8" osb to the joists? This is a good idea, if you can find some that's not too stiff - it will fill voids and help level things for less possibility of rattles. - what kind of screwing convention should i use for the three layers of flooring? Same as a wall; half-schedule for all but top layer. I would go 8" centers for top layer, 16" for under layers, and of course mark where first layer screws are and use longer ones for successive layers. - and regarding this Quote: Multiple floor layers should be at 90 degrees layer to layer, and cracks caulked before the next layer. Don't caulk til just prior to adding the next layer, so the next layer will flatten the caulk bead and pull down tighter. then how does the roofing roll come into play? how do i attach that and do i caulk that as well? using the roof roll, the floor layers will not actually be in contact with each other. I'm not sure roofing roll is such a good idea - especially if your studio has only one exit. Acoustically it should go between each layer, but I'm not big on flammable stuff in a 1-hole box. With 3 layers, I think I'd just forget it; with two, maybe get some of the real MLV. Don't forget to overstuff the insulation some - you want your first layer to compress the insulation by enough to place medium pressure on the panels to kill resonance... Steve

jeffjazz wrote:

- when should the tyvek be applied, or do i really need it? Jeff, You need a vapor barrier - and Tyvek House Wrap is NOT a vapor barrier - so please do not use this for that purpose. Tyvek is made to be installed on the outside of a house - and thus it has to breathe......... Vapor barriers (typically) go on the inside of the house - and should not breathe. To be an effective vapor barrier, a material needs to have a perm rating of 1.0 or lower - Tyvek House Wrap has a perm rating of 58. You can see that here: http://construction.tyvek.com/en/HomeWr ... lGuide.doc Also, this from the manufacturer:

Protecting against moisture damage Your walls can trap moisture that enters from outside through rain and moist air infiltration. From inside your home, cooking, humidifiers, dryers, bathrooms, range hoods and more add to trapped moisture. Without a means of escape, moisture can promote the growth of mold and mildew and begin to degrade wall materials. Left undetected, such moisture damage can affect the indoor air quality. With a housewrap like Tyvek® that breathes, trapped moisture vapor escapes safely to the outside. A breathable housewrap helps dry out any water or moisture in your walls.

Take care, Rod

sweet. 8) i'll make a diagram of where each layer's screw's are. my slab is dry. i haven't had a problem with moisture whatsoever. nonexistent. when i washed my garage out before starting all this, it dried fine. i'm just taking precautions... is the tyvek necessary in my case? btw my studio will have 2 exits. one in the control room leading to the house, and one in the tracking room leading to outside. would you still stick with the one layer of MLV(?), or would you go w. a roofing roll sandwich? which is better, or is this a moot point since i'll have 3 layers? i'm going to overfill the joists w. an added layer of R-19... but i could only get it with the face on it, not unfaced as you suggested. which side should the facing go on... up towards the sub floor or down towards the 4" roxul? thanks!! :lol:

Jeff, first of all please stop using the word "TYVEK" - Rod pointed out what I forgot to stress, (Thanks again Rod, you always got my back) that Tyvek is NOT a VAPOR barrier, it's an AIR barrier. What you want there is something like 6 mil black poly, also referred to as "visquene" - With three floor layers, I'd just skip the "snake oil" stuff. Be careful overfilling - if your roxul comes within 2" of touching a flat board laid across the joists, I'd cut the R19 into half-width strips - this will also have the effect of minimising any "triple leaf" effect caused by the paper. Then, I'd put the paper toward the roxul to keep it from contact with the poly VAPOR barrier on top, and finally add the floor layers. If you put TOO much insulation in, you will lessen the isolation of the floated floor; you want just enough overfill to damp the centers of the floor layers... Steve

Thanks Rod & Steve! 6 mil black poly as a vapor barrier on top of the R19 (which is cut in half and paper side down). allright, gotcha! :wink: do i want to staple the poly down or will the pressure of the boards keep it in place? i'll have updates soon, thanks guys!!!

shoot, i have one other question for now... what should i use as the floor boards? i previously planned to use: - 5/8" osb - 5/8" gypsum or concrete board - 5/8" osb but shouldn't i vary up the thicknesses of the materials as you have recommended in your "floating floor over basement concrete" sticky? in that post you recommended layers of 5/8" 3/8" 1/2" what shoud i use for my situation? thanks!

knightfly wrote:

Then, I'd put the paper toward the roxul to keep it from contact with the poly VAPOR barrier on top,

Steve- One comment here - This method places 2 vapor barriers in the system - and one of those is on the cold side of the assembly. If moisture comes in contact with this while inside the cavity it will condense - and the condensation will be absorbed by the insulation (because the vapor barrier won't allow it to escape) - eventually it can get wet enough so the insulation becomes useless - as well as being a perfect breeding ground for mold. An unfaced insulation would be better suited with the use of a poly vapor barrier I think. Rod

thanks rod! so then i should remove the facing of the R-19 and cut in half to properly overfill the floor... then add the vapor barrier?

Rod, you're right but I was thinking that since it would only be half width (in order to keep from too much fill causing too much coupling) that it should be OK - whaddaya think? (I agree that best would be to remove paper or find unfaced, just curious if you think that half-width strips just to obtain some compression for damping would still cause the double barrier problem... Steve

new pics :D rubber pucks of neoprene

control room floor 2x4s on neoprene w. rigid insulation around the perimeter.

floor detail filling is w. roxul

Jeff, can't tell from the pix; what kind of perimeter isolation board are you using to ensure that your floated floor can NOT come in hard contact with the walls? Also, from the look of it you may only want about 1/4 width strips of that R19 insulation over the roxul - it looks to me like the roxul is already almost exactly flush with the tops of the joists? If so, using too much extra R19 could cause too much compression and a resulting loss of isolation... Steve

hey steve, got it on the 1/4 panels. around the perimiter is 1" rigid foam insulation - scoreboard type.

Cool, thanks... Steve

do you have any ideas regarding the garage door? Here's what i was thinking: since i have to keep the door in place, i'll insulate it w. rigid insulation, then build a wall in front of it on top of the floating floor. the wall would be a John Sayers "inside out" type wall. this would keep to the m-s-m principle w. only 2 leaves 1. insulated garage door 2. drywall panels of tracking room what do you think?

jeffjazz, On my garage door for the 5.1 postproduction in garage this is how we did it. We disassembled the door took it off of the tracks and built a new frame 3.5 inches from the opening on the outside from 2x2's. Then reassembled the door (without the tracks) and screwed it to the new frame. This left the door pushed out towards the exterior by 3.5 inches. Most garage door jambs can accommodate this without it looking to wierd. This left a cavity that a 2x4 wall was built into 16 on centers filled with roxul. We built the wall on the floor and sheet rocked it with one layer of 5/8's. A winch was used to lift it into place to fill the cavity. VERY heavy! So what I got (from outside to in) is a garage door, one layer of 5/8 rock on 2x4 framing filled with roxul, 1 inch air space, a steel stud 24 inches on center wall on the floating floor filled with roxul and 2 sheets of 5/8's rock. I did a test yesterday with a sound source peaking in the high 90 db range and by the time I got ten feet from the garage door I could barely hear anything. If you like I can take measurements with my SPL meter. The only bummer is if that space becomes a garage again a whole new door would have to be purchased. You have to cut the top off the top panel to push the door outside the opening. Thanks, Dave

thanks, dave! i read your entire post "5.1 garage" and it was very helpful as your situation is kinda similar to mine. looks like the garage door will be one of the last steps as i want to use the door to get all the other materials in first. how did you stand the walls up? did you end up connecting them to the ceiling via a sway brace or did you just connect the joists directly and use RC? also, i'm still not sure if i should staple the vapor barrier in place or not? this site rules! 8)

Dave, your description - "So what I got (from outside to in) is a garage door, one layer of 5/8 rock on 2x4 framing filled with roxul, 1 inch air space, a steel stud 24 inches on center wall on the floating floor filled with roxul and 2 sheets of 5/8's rock."- Leads me to believe that (depending on the type garage door you have) your LF TL might be not as good as it could have been - from your description, if your door was one of the typical "raised panel" types similar to the pic of Jeff's (page 2 of his thread I think) that the thinner panels would leave a bunch of separate air cavities between the panels and the adjacent sheet rock layer - is this correct? I'm glad you're getting fairly good iso with a 90 dB source, but I wonder about the LF a bit here. One possible (even heavier :cry: ) 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. Then do the inner frame and wall as Jeff did, leaving as wide a gap (up to maybe 12" as you can stand between the inner and outer walls - this helps lower m-a-m resonance, which goes directly to better LF TL, which is almost always the problem area in wall limitations... Steve

steve, thanks for catching that... i was wondering a little about the cavities of the garage door and how they would play a part in a double or potentially triple leaf design. i like the idea of filling up the garage door so it would be a single solid heavy leaf. i was just going to fill in the cavities with remainders of rigid insulation until it was flush, but once again, you have come up with a better idea. i just figured dave's door was wooden or some other type that doesn't have the cavities that mine does. that will be a much later step, close to the final step, but do you have any advice regarding the vapor barrier? is the red poly that is available from home depot ok? do i staple it first then add the floor, or will the weight of the floor keep the poly in place? (i don't want to create unneccessary holes in the poly) thanks again!!! :lol:

Steve, The back of the garage door was foam core with a 1/16 inch metal frame holding the foam in place, no raised panels. Lots of caulk was placed in the foam area to minimize the 1/16th gap. The source was a buddy playing a drum kit. I do admit it is not a measred test but I was pleased with the results and I'm sure my neighbors will be as well.

how did you stand the walls up? did you end up connecting them to the ceiling via a sway brace or did you just connect the joists directly and use RC?

The connection method was pretty interesting. A take off of the brace. My father-in-law knew a source for 1 inch diameter neoprene grommet. So we placed braces betewen the rafters, drilled a 1" hole in the brace and placed the grommet up into the hole. Then drilled a hole in the top plate ran a bolt through the the hole in the top plate up through the grommet. Washers where used on each end and used a nut to tighten and squeeze the grommet a little. This allows for about 1.5 inches of movement for my roof rafter system. Which for me is critical if I get a big snow load. Again maybe not the best but the engineer thought it was very clever and workable. I can't take credit it was my father-in-laws idea. If you can do the brace thing you would probably get better isolation. I'm a rookie here. Sorry for the hasty explanation I'm at work. Gotta do T.V. now. Thanks, dave

Dave, glad your door wasn't like Jeff's; didn't remember if I'd seen it, this place is getting like a zoo. In Jeff's case, those deep gaps could be nasty little holes in an otherwise good idea... Steve

:o wow, it has been quite a zoo in here! i guess the good word is spreading! i can't find the answer to this anywhere... do i have to staple the vapor barrier down, or do i glue it, or just let the weight of the floor panels hold it in place?

Stapling is fine, just don't get carried away - your screws thru the flooring will penetrate also, so enough staples to hold things in place won't make any diff... Steve

great, thanks! :D i plan to lay the R-19, vapor barrier and 3 layers of flooring in the control room this weekend. hopefully i'll have pix for you soon! have a great weekend.... go colts! :lol: