John Sayers' Recording Studio Design Forum Archive

Anyone know where to get 703 in MD? Lowes is a OC dealer but from what the counter guy said, cannot carry it. Get this, he was on the phone with an OC rep. asking about availability and the rep. asked him if I heard about this online at a sound design forum!!! He says he gets calls all the time for this reason, but wouldn't say why they won't sell it to Lowes.

Any help? I'm in Southern MD.

Thanks,
TOM

I'm West Coast, closest thing I have listed to you is

Lancaster, PA
717-397-4014
717-397-3668
lancaster@spi-co.com

from the listings in the building products forum; keep in mind that Certainteed, Johns Manville, Knauf, and a couple others all have similar products; rigid fiberglass, mineral wool, slag wool, rock wool, all have nearly identical acoustic properties and are available in the 3 PCF range that's best for most acoustic use - and from what I've heard, some of those companies are MUCH more willing to sell to small markets than Owens Corning is... Steve

Thanks for the reply Steve

That's about 165 miles from my domain. I think I've found a Rockwool dealer that's a little closer, so I think I'm going to go with wall #343 in the NRC-CNRC Gypsum Board Walls: Transmission Loss Data papers. STC65

Now, this one uses 2 leaf construction = (2) 5/8" sheets of drywall with only 1-5/8" metal studs with 1-5/8" mineral fiber then a 2-1/2" air gap then the same for the other leaf (reversed of course).

The TL data looks pretty good to me, considering it is a very compact wall to achieve that rating.

Do you think it will really get these specs. in your experience (With only a little better than an inch and a half of insul. on either side.) It would definitely make the walls less expensive.

The only real problem I can see with that wall is fixing a door to a 1-5/8" frame. I guess I could double the track on the door side leaf and add another set of studs for the jamb. I dunno, sounds flimsy.

What do you think

Thanks,

TOM

They have heavier studs for some thicknesses that are used for door frames, but I agree it sound a bit thin - I've done very little framing with steel, and recently came across ANOTHER reason NOT to use it in climates like yours and mine - moisture control.

I don't have a link to this info yet, but one article I recently read talked about moisture control in buildings; basically, it referred to the level of moisture that was acceptable before it starts to cause problems (mold, rot, etc) - they gave three examples, all of a 2000 square foot house; the first, gypsum cladding and steel framing; the second, wood cladding and wood framing; the third, concrete block and other masonry.

The allowable moisture content of the entire house before problems - for the steel/gypsum, 5 gallons total; for the wood, 50 gallons; and for the masonry, 500 gallons;

Since reading that I've not recommended steel stud construction to anyone outside of the arid southwest USA.

If you intend to keep your space dehumidified, you could make this work; without that, I'd start looking for more space for thicker walls, and use the old standby double frame 2x4 with double 5/8 on one side of each frame.

If you'll look at the LOW frequency TL of your wall choice, you'll see where it "falls down" - this is where you pay for your lack of air gap, and this is where your neighbors learn to hate you if you're playing drums.

Just a thought... Steve

WOW! That's a juicy (pun intended) tid-bit of info...5 gallons? Definitely makes me re-think this wall. I've done constuction in area schools which use exclusively metal stud. Wonder if they've read the study?

OK, I think I'll go with wall #332. It's consistently 3 db to the plus across the spectrum.

Thank you for your wisdom. I never would have even considered that factor if not for this forum.

Steve, once again, above and beyond the call.

Gratefully,

TOM

Knightfly:
I'd be interested in that if you ever find it.

There's a thread about steel vs wood over at http://www.avsforum.com/avs-vb/showthre ... ost4829182 but there's nothing surprising there. Although it was pointed out that mold does not grow on steel studs.

I was just watching a "Holmes On Homes" episode, which is shot in Burlington Ontario, and he said about steel studs in the basement, "They rust. And they conduct hot and cold, so if any part of the wall is near anything cold, then the whole room gets cold"

Guys, here 'tiz - slurp it up while ya can

http://www.buildingscience.com/resource ... ldings.pdf

That site alone could account for a few evenings' reading, I'm still wading thru most of it... Steve

Hmmm....

Wondering how much dead (live?) weight moisture is actually adding to our calculations for ceilings? Especially to a couple layers of 5/8 drywall on RC. I guess it would bring the spring factor a little closer to it's limit at times.

TOM

Yeah, since the live/dead thing includes the weight of the framing as well as the cladding; although not as many use steel ceiling framing as do walls... Steve

Hi,

This company

http://www.mccormickinsulation.com/index.htm

sells Johns Manville insulation

Knightfly posted this:

from the listings in the building products forum; keep in mind that Certainteed, Johns Manville, Knauf, and a couple others all have similar products; rigid fiberglass, mineral wool, slag wool, rock wool, all have nearly identical acoustic properties and are available in the 3 PCF range that's best for most acoustic use - and from what I've heard, some of those companies are MUCH more willing to sell to small markets than Owens Corning is... Steve

They have a couple locations around Maryland. I'm heading up to one now.

- John Shryock