Will she hold, captain?!

How thick should my walls be, should I float my floors (and if so, how), why is two leaf mass-air-mass design important, etc.

Moderators: Aaronw, sharward

Manfriday
Posts: 18
Joined: Wed Oct 15, 2003 1:36 am
Location: St Charles Illinois

Will she hold, captain?!

Post by Manfriday »

I know I we be soundly beaten with a trout for not finding this out sooner, but I think I discovered this site a little too late. heh.

Anyway. Im working on a little studio in my basement. Nothing too fancy, but I am putting some money into insulation and drywall to keep transmission noise from upstairs to a minimum.

Too many of my recordings have little voices in the background shouting "DADDY! HE BIT ME!" and other such things..

I digress..

So I put up some 1x3 furring strips to get around a couple obstacles, slapped up the resillient channel, stuffd the space between the joists (16") with some R30 and I went out and boughta butt-load of 5/8 drywall and some 1/2 celotex.

As I am lugging the drywall in it is dawning on me just how damned heavy this crap is.

My plan was to screw the 5/8 DW into the RC, slap on the 1/2" celotex and then but on another layer of 5/8" drywall.

So my question is.. what is the likelyhood of me being killed in a tragic recording studio accident?

I probably have the RC too far apart for this.. It is all screwed in about 14" from the center of one RC to the next.

If you dont think the ceiling can handle the weight of 5/8.cel.5/8 what other options do you think I should persue?
Again, I have to balance what is "right" with what I can get away with.
damned wife and her worries about feeding the children. bah! let them eat cake!
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

Cake is cool, long as it doesn't cover up the taste of the pizza, then it becomes unhealthy...

You didn't mention the vertical depth or the span of your ceiling joists (vewy importante), but your RC is actually plenty close (unless it's the wimpy, wall-only kind)

For 3-layer ceilings, RC on 16" centers is plenty close even if all 3 layers are sheet rock. Use Wood type screws fastening the RC, and use at least 1-1/2" long to fasten the RC to the joists. Where you're fastening to furring strips instead, it could be different. Are your furring strips parallel to joists or perpendicular? How sturdy are their fastenings to joists? If none of this is a weak link, and you use a 12" spacing on screws holding the paneling to the RC (staggered 4" each layer) you should be fine.

Still need vertical depth AND span of your joists so I can tell you whether to stay put, or only record "smashing pumpkins" down there... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
Manfriday
Posts: 18
Joined: Wed Oct 15, 2003 1:36 am
Location: St Charles Illinois

Post by Manfriday »

Ok.. Im not entierly sure I follow your banter sir. (forgive the monty python reference) but I will do my best to answer your questions..

the joists are 9" deep.
IM not sure what you meant by the span of my cieling joists..
measuring the room parallel to the joists is about 11'1"

the room is actualy 11'1x16 if it matters.

I did use 1 1/2" wood screws to screw the RC in.

the furring strips I did along the length of the joists (which would be aprralel i guess) rather than across them. I hope that was right. I really am not a carpenter. I only play one on TV.
I used 1 5/8" scrwes and liquid nails for attaching the furring strips. I glued and screwd the snot out of them.

thanks for your help!

J
giles117
Senior Member
Posts: 1476
Joined: Sat Jun 21, 2003 2:42 am
Location: Henderson County
Contact:

Post by giles117 »

You should be fine then. Rc is quite strong considering it's flexibility. :)

I Only wish you had put in some Roxul AFB in that ceiling instead of Just R-30 (Possibly R-19)

Bryan Giles
Manfriday
Posts: 18
Joined: Wed Oct 15, 2003 1:36 am
Location: St Charles Illinois

Post by Manfriday »

hmm. well I have some R19 laying about the place. or if I needed to I could go grab a couple more bags of R30.
and stick that in there too.

I didnt because I thought some air between the floor above and the insulation was a good thing?

not sure what Rockwool is though?
giles117
Senior Member
Posts: 1476
Joined: Sat Jun 21, 2003 2:42 am
Location: Henderson County
Contact:

Post by giles117 »

The issue is for density, the denser the matarial (as long as it not too dense) the better. AFB from roxul, or rock wool, mineral wool, etc... is denser than the pink stuff therfore cutting down sound transmission more effectively.)

www.roxul.com they are a canadian company.

Bryan Giles
giles117
Senior Member
Posts: 1476
Joined: Sat Jun 21, 2003 2:42 am
Location: Henderson County
Contact:

Post by giles117 »

I guess I should add this, what you have done is fine if it's already done. Don't Sweat it. The difference is marginal.

Bryan Giles

BTW the way I thought R-30 was 9" thick? Maybe I am wrong. :)
Manfriday
Posts: 18
Joined: Wed Oct 15, 2003 1:36 am
Location: St Charles Illinois

Post by Manfriday »

heh. the stuff I got says it is 10 1/4" thiick, so I guess the whole idea of air between the insulation and the floor above was kinda pointless.
Good thing I dont do this for a living!
:oops:
giles117
Senior Member
Posts: 1476
Joined: Sat Jun 21, 2003 2:42 am
Location: Henderson County
Contact:

Post by giles117 »

You got what I was hinting at huh? LOL

The AFb comes in thickness of 1.5 to 4" and is way more effective at absorbing sound. Oh yeah, and It's cheaper to according to my cost estimates. I did an entire ceiling 10x13 for about $30 dollars using 3" AFB. The sheets (2'x4') costs 56 cents a sheet.

Bryan Giles
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

Looks like you're in good shape all around - if your joists measure 9", they're most likely 2x10's which are usually an ACTUAL 9-1/4" deep. They are plenty strong enough for the weight of 2 drywall and 1 sound board layers.

Bryan covered the rest, so you should be good to go... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
Manfriday
Posts: 18
Joined: Wed Oct 15, 2003 1:36 am
Location: St Charles Illinois

Post by Manfriday »

Well, a buddy of mine and myself spent from 6 pm to 12:30 am
putting up that ceiling.
1 layer of 5/8 , 1/2 celotex, and another layer of 5/8.
My body feels like a train hit it. It's hell getting old(er).

I had no idea how claustrophobic 7'2" feels. Seems like the lack of trasmission noise from upstairs is pretty good now though. Im pleased.

now I need to do the walls. Im going to do RC on one side of the wall.

Do you think I'd be better off using 3 layers of drywall on each side? or doing the same thing I did with the ceiling?
(i.e. drywall, celotex, drywall?)

R13 insulation seem ok for the walls? or should I look for this magic fur that Giles was talking aboot? Where does one get this sort of thing? Home depot and Menards are the only worlds I know!

thanks a bunch guys

Jason
giles117
Senior Member
Posts: 1476
Joined: Sat Jun 21, 2003 2:42 am
Location: Henderson County
Contact:

Post by giles117 »

Jason,

Well if this helps, I ripped all the R-13 I had put in my walls out and redid the walls with the Roxul.

I Put in a call to Roxul to find a distributor in your area.

You will yield much better damping and absorption in your wall cavity with the AFB/Rockwool, etc.... Roxul is a subsidiary of Rockwool International. Just the North American branding is Roxul.

The Drywall/Celotex/Drywall is an excellent way to go. As Steve has described the difference in materials changes the way sound transmits which of course sound is like electricity always looking for the least path of resistance. In this case your are changing the components and thus improving your Transmission Loss.

Bryan Giles
giles117
Senior Member
Posts: 1476
Joined: Sat Jun 21, 2003 2:42 am
Location: Henderson County
Contact:

Post by giles117 »

Here yah go...

Bob Turley
708-287-4907

Crystal Lake, IL

He carries the AFB and the RHT-40 products.

I'd recommend the 3" AFB for the inside of your walls


See people, this is why we need you to fill in the location part of your profile.

So we can help research distributors and such like for yah.

Bryan Giles
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

Thanks for that Bryan, please be sure to post it in the Materials area - this kind of info is at least as helpful as the "how" part... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
Manfriday
Posts: 18
Joined: Wed Oct 15, 2003 1:36 am
Location: St Charles Illinois

Post by Manfriday »

thanks so much Bryan! that was certainly above and beyond the call.
what a great board. :)

And thank you too steve, for the info!

:)
Post Reply