Is this the correct item I should get?
F.C.1-TRU 25 GAUGE RESILIENT SOUND CHANNEL
http://www.phillipsmfg.com/Channels.htm
RC Channel
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cfuehrer
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giles117
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I bought it, but Steve recommends the Auralex RC-8 or similar stuff because only about 25% of the channel that the drywall screws into is attached to the plate that you screw into the wood.
It saves about 2-3db he speculates. Hmm STC 55 or 52. Doubt I'll notice it for my application.
Bryan Giles
Pics to follow
It saves about 2-3db he speculates. Hmm STC 55 or 52. Doubt I'll notice it for my application.
Bryan Giles
Pics to follow
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cfuehrer
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giles117
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More info from Phillips.
A wall consiting of 5/8" gypsum (single layer). 3.5" metal studs 3" Rcockwool with RC gave an stc of 50.
The Rc Specs are as follows
.0209 thickness
1.25" Face width (drywall side)
.5" Ht of leg (rise)
.44 Flange width (Wood stud side)
TL Loss Specs on above design wall
Freq TL (in db)
125 29db
160 35db
200 39db
250 44db
315 46db
400 46db
500 48db
630 50db
800 52db
1000 53db
1250 52db
1600 54db
2000 54db
2500 47db
3150 50db
4000 54db
They found the same STC of 50 if the wall was loaded with OC R-11 3.5: Pink Insul
TL at lower freq was better by 1db Same metal wall construction.
So I would assume that this lit shows that it is comparable to what the RC-8 gives you So Do what I did, buy with confidence the Phillips. It is so much cheaper
so if you build according to the specs in the house, you should end up with a loss of 54+
Bryan Giles
A wall consiting of 5/8" gypsum (single layer). 3.5" metal studs 3" Rcockwool with RC gave an stc of 50.
The Rc Specs are as follows
.0209 thickness
1.25" Face width (drywall side)
.5" Ht of leg (rise)
.44 Flange width (Wood stud side)
TL Loss Specs on above design wall
Freq TL (in db)
125 29db
160 35db
200 39db
250 44db
315 46db
400 46db
500 48db
630 50db
800 52db
1000 53db
1250 52db
1600 54db
2000 54db
2500 47db
3150 50db
4000 54db
They found the same STC of 50 if the wall was loaded with OC R-11 3.5: Pink Insul
TL at lower freq was better by 1db Same metal wall construction.
So I would assume that this lit shows that it is comparable to what the RC-8 gives you So Do what I did, buy with confidence the Phillips. It is so much cheaper
so if you build according to the specs in the house, you should end up with a loss of 54+
Bryan Giles
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knightfly
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It's not just the gauge, but the percentage of perforation of the "riser" portion of the RC - the original RC-1 by USG and the current RC-8 by "Aural-Extra-Expensive" have about 25% coupling between the flat surface that mounts to the studs and the flat surface that mounts to the drywall. That single factor seems to be what improves isolation, although gauge would certainly be a factor.
I don't think I would personally feel too comfortable in a room with 3 layers of drywall overhead mounted on ANYBODY's RC - I would personally tend more toward the heavier leaf of a 2-leaf wall or ceiling being mounted solid to the studs, and just putting two layers of 5/8 firecode sheet rock on the RC. It kind of depends on how much isolation you really need, and whether you can MATCH it with your glass, doors, HVAC, flanking noise, etc - if not, it's a moot point at best.
In any sound barrier, the primary task is getting two leaves of mass separated by one air space, with ZERO hard coupling between the two leaves. It helps if each leaf has different characteristics, since any frequency that excites BOTH leaves will pass thru with the least attenuation.
Because of these factors (and probably several others that are subliminally influencing my "gut feel"), my idea of a good sound wall would be two separate frames, the side toward the heavy bass source being 16" (or even 12") centers with (starting at the studs) 5/8, 3/8, 1/2" drywall, NO RC on that side, first layer (if wood studs) screwed to studs, then all successive layers strip-glued in-line ONLY at a line parallel to (and offset from) studs by about 2", and fastened with laminating screws (Type G), ALSO offset same distance and direction - you want the glue line and the laminating screws to miss the studs by about two inches, and in the same line for both additional layers - this gives each panel its own resonance, which because they are DIFFERENT will reduce coincidence dip effect - it also eliminates the flanking caused by screws through outer layers of wallboard into studs. (This doesn't apply as much, if at all, with metal studs since their inherent flexibility lessens transfer)
If using metal studs, you could optionally just screw each layer of wallboard to the studs, although it might be slightly better to use the same method as with wood studs, above.
For the second frame, I would either use wood studs on 24" centers or, if I couldn't get RC and COULD get steel studs, use light gauge (25) so they flex enough to make up for the lack of RC - preferably, I'd stay with wood if the other side was wood, and put RC and two layers of (screwed only) 5/8 sheetrock, firecode if it's available (slightly better STC)
As always with RC, if you goof EVEN ONCE and put a screw thru the wallboard and into a wood stud, you will lower isolation by enough to almost totally NEGATE the use of RC at all. I've read of walls being tested and dis-assembled, only to find that as many as TWENTY screws were "shorting out" the RC - a good argument for marking stud/joist locations before putting up wallboard.
For insulation, knowing what I know now I'd use 2-3" 703 in between the frames, and fiberglas batts (possibly the newer "high density") slightly compressed against the panels, between the studs just like standard house construction, but with some compression (use next size thicker batts than stud cavity depth) -
With ANY sound wall construction, you want ZERO penetrations if possible, and definitely NO BACK TO BACK ones. Best electrical is surface mount, second best is offset boxes (by at least one cavity, preferably two) and total caulking of boxes.
If using surface mount wiremold, I'd put it just below any wall treatment so it almost disappears. I don't recall what the minimum height for outlets is to meet code, but you should conform to that whatever it is.
Most (if not all) the rest of wall construction has been covered to death in other threads, hopefully some time in the near future I'll get a chance to finish the FAQ and basic drawings project, so this can all be in one place... Steve
I don't think I would personally feel too comfortable in a room with 3 layers of drywall overhead mounted on ANYBODY's RC - I would personally tend more toward the heavier leaf of a 2-leaf wall or ceiling being mounted solid to the studs, and just putting two layers of 5/8 firecode sheet rock on the RC. It kind of depends on how much isolation you really need, and whether you can MATCH it with your glass, doors, HVAC, flanking noise, etc - if not, it's a moot point at best.
In any sound barrier, the primary task is getting two leaves of mass separated by one air space, with ZERO hard coupling between the two leaves. It helps if each leaf has different characteristics, since any frequency that excites BOTH leaves will pass thru with the least attenuation.
Because of these factors (and probably several others that are subliminally influencing my "gut feel"), my idea of a good sound wall would be two separate frames, the side toward the heavy bass source being 16" (or even 12") centers with (starting at the studs) 5/8, 3/8, 1/2" drywall, NO RC on that side, first layer (if wood studs) screwed to studs, then all successive layers strip-glued in-line ONLY at a line parallel to (and offset from) studs by about 2", and fastened with laminating screws (Type G), ALSO offset same distance and direction - you want the glue line and the laminating screws to miss the studs by about two inches, and in the same line for both additional layers - this gives each panel its own resonance, which because they are DIFFERENT will reduce coincidence dip effect - it also eliminates the flanking caused by screws through outer layers of wallboard into studs. (This doesn't apply as much, if at all, with metal studs since their inherent flexibility lessens transfer)
If using metal studs, you could optionally just screw each layer of wallboard to the studs, although it might be slightly better to use the same method as with wood studs, above.
For the second frame, I would either use wood studs on 24" centers or, if I couldn't get RC and COULD get steel studs, use light gauge (25) so they flex enough to make up for the lack of RC - preferably, I'd stay with wood if the other side was wood, and put RC and two layers of (screwed only) 5/8 sheetrock, firecode if it's available (slightly better STC)
As always with RC, if you goof EVEN ONCE and put a screw thru the wallboard and into a wood stud, you will lower isolation by enough to almost totally NEGATE the use of RC at all. I've read of walls being tested and dis-assembled, only to find that as many as TWENTY screws were "shorting out" the RC - a good argument for marking stud/joist locations before putting up wallboard.
For insulation, knowing what I know now I'd use 2-3" 703 in between the frames, and fiberglas batts (possibly the newer "high density") slightly compressed against the panels, between the studs just like standard house construction, but with some compression (use next size thicker batts than stud cavity depth) -
With ANY sound wall construction, you want ZERO penetrations if possible, and definitely NO BACK TO BACK ones. Best electrical is surface mount, second best is offset boxes (by at least one cavity, preferably two) and total caulking of boxes.
If using surface mount wiremold, I'd put it just below any wall treatment so it almost disappears. I don't recall what the minimum height for outlets is to meet code, but you should conform to that whatever it is.
Most (if not all) the rest of wall construction has been covered to death in other threads, hopefully some time in the near future I'll get a chance to finish the FAQ and basic drawings project, so this can all be in one place... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
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giles117
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As promised here is a pic of my construction of the live room ceiling
This is the 1st layer, studs mounted to ceiling, RC mounted to studs, you will notice here that this pic was taken before the rc was completely secured. I used 1.5" Rockwool/SAFB
Next will be a 5/8" sheet then a sheet of 5/8" celotex then 1/2" Drywall.
Will post as it goes in.
Bryan Giles
This is the 1st layer, studs mounted to ceiling, RC mounted to studs, you will notice here that this pic was taken before the rc was completely secured. I used 1.5" Rockwool/SAFB
Next will be a 5/8" sheet then a sheet of 5/8" celotex then 1/2" Drywall.
Will post as it goes in.
Bryan Giles
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knightfly
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giles117
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I have to disagree with you steve.
I am reading and following the advice in a letter dated 8/8/2003 from Phillips to Drywall Contractors
And I Quote:
Installation - Ceilings
"Resilient Channel should be attached at right angles (90 degrees) to wood trusses or joists on 16" centers. The open side of the RC should always be installed the same direction and attached at each intersection (lengthwise)"
Hope that helps you out.
Bryan Giles
I guess I should add:
the subject of the letter is as follows: Recommendations for Installation of Resilient Channel in Ceilings...
I am reading and following the advice in a letter dated 8/8/2003 from Phillips to Drywall Contractors
And I Quote:
Installation - Ceilings
"Resilient Channel should be attached at right angles (90 degrees) to wood trusses or joists on 16" centers. The open side of the RC should always be installed the same direction and attached at each intersection (lengthwise)"
Hope that helps you out.
Bryan Giles
I guess I should add:
the subject of the letter is as follows: Recommendations for Installation of Resilient Channel in Ceilings...
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knightfly
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Good enough for me... I thought I had read just the opposite in USG's construction manual, but just searched the entire manual and not a word either way. Also searched the entire Sound Contro Manual from USG, still nada - I know I read that somewhere, and it kinda made sense for ceilings - oh well, chalk it up to brain farts... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
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giles117
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jazzman
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Different companies have different instructions for mounting RC on the ceiling. When Unimast was bought by Dietrich, it caused even more confusion. I called two different guys in the two different divisions and they gave me two stories, which, as it turned out, were both right because their ceiling channel products were slightly different.
Unimast makes a product called RC-2 which has screw points on BOTH sides. These sides are connected to the main body of the channel by way of a web-like metal structure. With this product when you attach the channel to the bottoms of the joists (at 90 degrees) with screws, you are supposed to alternate the sides.
With the Dietrich product, all the screws go on the same side.
Go figure.
Lee
Unimast makes a product called RC-2 which has screw points on BOTH sides. These sides are connected to the main body of the channel by way of a web-like metal structure. With this product when you attach the channel to the bottoms of the joists (at 90 degrees) with screws, you are supposed to alternate the sides.
With the Dietrich product, all the screws go on the same side.
Go figure.
Lee