Stucco as mass?

Ok, so here's the latest question... Two walls of the garage I will be building my studio in are stucco, facing the garage interior. We'll be tearing the walls out that aren't shared with the house and rebuilding, so those aren't an issue. My guess is that if possible, I should rip the stucco out and then use the existing house interior wall as one of the masses, beefed up with a couple layers of whatever, then insulation, then my second wall. BTW, the brilliant builders that put up this house in the '60s didn't put insulation in the walls, so there is no insulation between the studs in the walls that the stucco is on. It would be easier and cheaper if I could just leave the stucco and add layers to it on the garage side. How much differece in TL are we talking between the two options? If we're talking about 2 or 3 db, I'll probably save the expense. Any other good options I'm not thinking of?

Here's the direction I'm heading at the moment, FWIW....

I'd recommend that the door to the main room swing inward. Also, bathroom doors usually swing inward.

Yeah, it's a rough mock up. The bathroom will probably be a pocket door... it's a pretty tiny space. You might be right on the control room... maybe in to the right is the way to go (from the entryway). Regardless, I'm sooo not that far yet... I'm talking with a CAD guy this week and just need to know what to tell him to draw as far as the walls.

Biggest problem for iso between houses/studios is normally LOW frequencies; this is also the biggest diff in isolation between 2 and 3-leaf partitions. I'd pull the stucco out unless your family likes "boom-boom" with their TV or reading or sleeping... Stucco has just a bit higher density than gypsum (50 PCF vs. 42), so from that standpoint it's OK. It's just that you'll lose somewhere around 8-10 dB or more at the low end by leaving that in place and making a 3-leaf wall. Do a search on gypsum inserts (Keith probably has a link to the better ones, Keith??!?) This is the way I'd go. couple layers of gypsum between studs and against your house side's paneling, then your inner wall layers on separate frames... Steve

Alright... that's what I was looking for. Thanks Steve.

Stick wrote:

You might be right on the control room... maybe in to the right is the way to go (from the entryway).

Exactly what I was thinking. :)

knightfly wrote:

Do a search on gypsum inserts (Keith probably has a link to the better ones, Keith??!?)

Hark -- do I hear an order for a link? :mrgreen:

Excuse me, Sticky, this has nothing to do with the thread... :oops: But I have to ask... Could you tell me which drawing soft is this you´re using? I think its fabulous... Thanks, sorry, and good luck on your work!! Chino.

Looks like Sketchup to me.. :roll:

Thank you, Sharward!! So, it´s the 'ketchup' then... hahahaha...!! :lol: Seriously, I think is really great... Thanks again! Chino.

Sketchup it is. Cool program... not too hard, even for us musicians. -The Stickage

knightfly wrote:

This is the way I'd go. couple layers of gypsum between studs and against your house side's paneling, then your inner wall layers on separate frames... Steve

Ok, so the stucco's going to go. That'll be me with the sledgehammer. All the rest of the outside walls we'll be rebuilding from scratch (the original builder did a few no nos. So, I was thinking of something like, from the outside, siding--styro--OSB (MDF?)--drywall--drywall--studs. Is that doable? It seems odd to be putting drywall on that side of the studs... Now on the inside of the house, on the wall where the fireplace is, I'm going to do our layers of drywall. I was sort of leaning toward stud--3/4" MDF--5/8" drywall--1/2" drywall. Is this overkill in a set up where I won't be floating the floor? (The studio and the living room where the fireplace is share the same slab.) On the other shared wall, I'm planning to do the same layers, but the MDF and first drywall layer will have to go between the studs on the garage side. It seems like the MDF first would be cool because then the drywall (and whatever else we hang on that wall) can just screw right into it. Once we get to the studio walls, I'm not planning to use RC, because I think I'd rather have the low end stop rather than a little better high end stop. I don't think hi end is going to be the issue for me. So, whachya'll think? Is three layers overkill? Maybe just 5/8" and 1/2" drywall? I'm foggy on the door/window TL comparisons to a wall like this. If I'm just doing solid wood doors, sealed of course, will they keep up with the 3 layers? Again, I'm not going for commercial recording studio isolation... I'm after good enough and cheap. Thanks for the guidance.

A little bump to get some opinions on the layers... Thanks, b

B, normal drywall doesn't have the racking resistance to be used on outside frames; there is a type of exterior rated drywall I've heard about but not used. If you're using some type of wood siding that won't leave air voids when used over another layer, I'd go with either durock in larger sheets or 3/4 OSB or wafer wood under the siding to get more mass in the outer leaf. I'm not clear whether these will be double framed walls; any chance of a sketch/diagram of some sort? also, unless you MUST because of code I'd NOT use foam - nearly zero mass, and puts vapor barrier in the wrong place for any but hot humid climate (with AC on nearly year 'round) - instead, if possible I'd do a Tyvek wrap on the outside, use either standard fiberglass or Fibrex/other SAFB's at 2.5 PCF density, leave a little gap between frames and do 2-3 layers of 5/8 gypsum on the inside (more insulation against the inner leaf for damping) - and of course caulk everything - somewhere around here there's a link to OSI 175 caulk for $3 a tube, can't beat that anywhere. For the rest of your questions, I'm gonna need a sketch of your intentions so I can see what you're asking about - need to see all frame locations and any/all paneling layers from outside to inside. Doors/windows - doubful if they will keep up with 3 layers, but this also depends on your positioning/framing. Sketch?? 8)

knightfly wrote:

. . . If you're using some type of wood siding that won't leave air voids when used over another layer, I'd go with either durock in larger sheets or 3/4 OSB or wafer wood under the siding to get more mass in the outer leaf.

Here are data sheets for Durock (by USG Corporation), and a similar/competing product called WonderBoard (by Custom Building Products).

The sketch up above in this thread shows the the basic layout and double walls and door and window locations (for the time being... nothing is built). Below is my guess at the layers... All of the walls that aren't the house (the left wall and the top wall in the sketch, and the half of the right wall) will be rebuilt, so we can do whatever we want exterior finish on in. A bunch of the rest of the house is stucco, but my wife's not crazy about it. We've looked at some cool Hardiplank stuff, but it's pricy. So, we don't know yet. Thanks, b

Awesome illustrations, Stick!! 8) What the purple stuff on the studs under the Durock/Wonderboard in the top image? :? --Keith :mrgreen:

I was assuming I should stick some regular insulation up against that side as well as on the inner wall. Maybe that's overkill? And thanks for the compliment on the drawings... it's just SketchUp. Too bad I don't know enough to really draw the "plans". It's making me crazy trying to get them drawn without busting the budget.

Stick wrote:

I was assuming I should stick some regular insulation up against that side as well as on the inner wall. Maybe that's overkill?

Again, I'm talking about the purple stuff on the surface of the stud. :? Maybe that's just a goof in Sketchup, but it looks to me like it's a tiny bit of something on the surface of the studs themselves between the studs and the Durock/Wonderboard. (Insulation? Rubber?) If so, then I think that's a mistake. Certainly insulation between the studs is good though.

Too bad I don't know enough to really draw the "plans". It's making me crazy trying to get them drawn without busting the budget.

What's the budget-busting aspect of it? Are you trying not to spend too much money on the software to be able to draw the plans? Or are you concerned that you'll have to pay someone to draw them for you? FYI, Steve has recommended that people do 3 layers of 5/8" drywall, rather than monkeying around with 3 layers of different thicknesses. The extra 1/8" in your case gives you a bit more mass, which is better for low-end TL -- plus, you don't have to worry about maintaining multiple thicknesses of panels on site -- especially beneficial when you have limited storage space for materials. 8) --Keith :mrgreen:

Ah, no, that's me forgetting to put the little "wood grain" color on that side of the stud. And, yeah. John gave me what is probably a very resonable quote to draw the plans, but it's just way more than I can spend. As far as the drywall, I think I will just do 3 5/8" panels on the inside... initially I was thinking the differing thinknesses helped with resonances, but I suppose witht the same material all the way through it wouldn't matter. And I thought if we could find unbeveled 5/8" (for the seams), and then use beveled 1/2" it might be slightly easier to keep track of which was which... probably doesn't matter. And space is not an issue. 1.4 acres to spread the love. Maybe I don't need someone to draw them for me, but I just really need to get it going soon... and I don't really have the hours of research to figure out everything I need to know. Like, the Air Conditioning set up... dealing with the attic joists and supporting two ceilings... span loads for the inner ceiling... blah blah blah. I guess I should just go for it, and run it by you guys and see... maybe I don't need too pay someone. It's just that everyday I spend working on this, is a day I'm not making music earning the money to pay for it. Hmmm.... what do you think? Can I do it? Thanks, b

Stick wrote:

Ah, no, that's me forgetting to put the little "wood grain" color on that side of the stud.

Ahhhh, nothing like having a silly little thing pointed out in public to boost the confidence level, eh? :lol: ;-)

And, yeah. John gave me what is probably a very resonable quote to draw the plans, but it's just way more than I can spend.

John's work is amazing, indeed. But, budgets are budgets... :?

As far as the drywall, I think I will just do 3 5/8" panels on the inside... initially I was thinking the differing thinknesses helped with resonances, but I suppose witht the same material all the way through it wouldn't matter.

I seem to recall seeing that there is a slight benefit, but I think the benefot of the "extra mass" outweighs that. (I'm just echoing what I think I've read before -- that's by no means an authoritative answer. :roll:)

And space is not an issue. 1.4 acres to spread the love.

:evil: You bastard! :evil: ;-)

Maybe I don't need someone to draw them for me, but I just really need to get it going soon... and I don't really have the hours of research to figure out everything I need to know. Like, the Air Conditioning set up... dealing with the attic joists and supporting two ceilings... span loads for the inner ceiling... blah blah blah. I guess I should just go for it, and run it by you guys and see... maybe I don't need too pay someone. It's just that everyday I spend working on this, is a day I'm not making music earning the money to pay for it. Hmmm.... what do you think? Can I do it?

You have a lot of company in your conundrum -- that's for sure. Fellow Northern Californian mikeklooster is one such animal. (And, having met him personally, I mean that in figurative and literal senses! :lol: ;) ) Your project is one of the more involved ones, in that it's an addition -- not a garage conversion, not a basement buildout, not the repurposing of existing space. So, in that sense, I can understand your hesitation. However, your limited budget being what it is, and seeing what you can already do with sketchup, I would think that you've "got what it takes" to put plans together and then post them here for the world to see and for all the experts here to tear apart to smitherines. ;-) I realize it seems like rather un-fun work (it is, at times), and that there's so much other stuff you'd rather be doing... But think of it this way: you'll have a lot more freedom to experiment and move things around on proverbial paper if you do it all yourself. You'll also force yourself to learn all the intricacies of the project -- which is so valuable, whether you actually do all of the construction work yourself or not. I realize I'm saying this a couple of weeks prematurely, so with that caveat... If I -- a web software guy who's to this day more than a little frightened of a circular saw -- can draw up plans and get a permit from a very scrutinous municipality, then surely you can. 8) We won't let you screw up, Stick. Heck, we'll spot that purple blotch a mile away! :lol: --Keith :mrgreen:

Well, you are encouraging... and besides, I'm about to fly overseas for a session in Poland, so there's a good 2 days of travel time to play with my plan. HA! Though running SketchUp drains the battery in a hurry! Actually, it is a garage conversion. So, that's where a lot of my air conditioning issues and space limitations come from. We don't really want to rip off the entire roof for this little endeavor. Though, now that I say it... maybe we should... it's a little saggy already. Heh heh. And though I'll do some of the work (more like "help") I've got a great contractor that'll do most of the real building. But, I do own a couple saws and I'm quite handy at demolition (should'a seen me swinging a little sledgehammer through the stucco the other night). Basically I just need a plan that he and I can build from. I'll also hire an HVAC guy to put in the system, but this is the area where I'm most sketchy for solutions. And looking at your nightmare with the ventilation stuff, I'm even more afraid. :shock: Ok, off to Lowes to pick up a bathroom door. (We've been remodeling the interior of the house for a year now...) BTW, have you found a place for Acoustic Caulk in Sac? I've got some on the way from elsewhere, but the shipping costs are a bummer. I ordered the Titebond stuff...

Stick wrote:

Actually, it is a garage conversion.

Oh yeahhhh -- I'm still stuck on your old original ultimate dug into the earth half bomb shelter half building standalone thing. (That was you, right?)

I'll also hire an HVAC guy to put in the system, but this is the area where I'm most sketchy for solutions. And looking at your nightmare with the ventilation stuff, I'm even more afraid. :shock:

Well, I think my nightmare ended happily. It won't be cheap, but I'm all but certain it will do the job and (here's the kicker) give me the required level of control of the system inside my space withot impacting the rest of the house. Once I stopped thinking of air conditioning and ventilation as the same issue, I was able to free my mind to come up with solutions to both separate issues.

BTW, have you found a place for Acoustic Caulk in Sac? I've got some on the way from elsewhere, but the shipping costs are a bummer. I ordered the Titebond stuff...

Have you checked with Acoustical Material Services' Sacramento location yet? Post back with what you learn, 'cuz I'll need some fairly soon (I hope).

sharward wrote:

Oh yeahhhh -- I'm still stuck on your old original ultimate dug into the earth half bomb shelter half building standalone thing. (That was you, right?)

Yeah, that was me. I still think that was a pretty cool idea. But the bread just isn't there for it.

Once I stopped thinking of air conditioning and ventilation as the same issue, I was able to free my mind to come up with solutions to both separate issues.

Yeah, that could be the way to go for me too...

Have you checked with Acoustical Material Services' Sacramento location yet? Post back with what you learn, 'cuz I'll need some fairly soon (I hope).

No, good lead though... I hadn't found them. I'm calling right now... I might go grab some now if they have some in stock... the wall we're working on this week in the house needs some sealing, as it backs up to the soon to be studio.

Have you checked with Acoustical Material Services' Sacramento location yet? Post back with what you learn, 'cuz I'll need some fairly soon (I hope).

Well, I called 'em up, and then ran down there to get some caulk, which they obviously had in stock. And it was cheap. 7 bucks for 3 29oz tubes. I'm feeling like an idiot for ordering the Titebond stuff from Virginia. Oops. Oh well, at least I'll be able to give first hand advice on which one is better. It looks like they've got a lot of stuff in stock. 703, Roxul, doors, etc. And sounds like they can get whatever as well. I think they'll be a good resource. Though, they didn't have much in the way of quiet HVAC parts. And I'm leaning back toward designing the whole deal myself with the help of my new best friends on the RSDF. 8) Away we go! I'm going to redraw from scratch on a more carefully measured starting point, so perhaps I should start a new thread? Thanks... b