Author Topic: Fiber vs. Cotton: The facts  (Read 4438 times)

johnbergstromslc

  • Guest
Fiber vs. Cotton: The facts
« on: October 06, 2006, 09:00:54 PM »
Cotton is being touted as the 'superior' insulation in soundproofing applications.  You decide for yourself.

Fiber test:  NRCC (National Research Council of Canada), TL-93-157

Cotton test: Acoustic Systems, AS-TL1766

Both tests involved standard stud walls, 16" o.c., with the respective insulation in the cavities (R-13).  5/8" drywall was applied to each side, with similar fastener spacing.  In the NRCC test, the joints were taped and mudded in the usual manner, while the acoustic systems test duct taped their joints.

Here are the TL results (in dB):

Hz          Fiber       Cotton

50          22.3        22
63          18.5        21
80          23.2        18
100        18.1        17
125        13.0        19
160        12.7        15
200        25.0        17
250        37.9        32
315        35.8        36
400        36.1        31
500        39.4        32
630        44.2        40
800        43.2        41
1000      46.7        42
1250      47.4        44
1600      46.8        41
2000      40.2        36
2500      37.4        36
3150      42.5        40
4000      47.8        43
5000      52.9        47
6300      57.2        51

STC        34           35
OITC       29           26

Since most people cannot discern less than a 3 dB change in the sound level, the differences are trivial.  You don't itch with cotton and don't have to wear any protective clothing (but a mask might be a good idea) but is that worth paying 4 times as much?  Maybe sometimes it is.  But otherwise, it's not something to worry about.          





hickory_stick

  • Guest
Re: Fiber vs. Cotton: The facts
« Reply #1 on: October 08, 2006, 06:34:51 PM »
Is the cotton tested the same as found in your medicine cabinet?  Handfuls of that stuff might not perform as well as the "treated fiber product" (UltraTouch) made by Bonded Logic in their patented process.  

Hick

johnbergstromslc

  • Guest
Re: Fiber vs. Cotton: The facts
« Reply #2 on: October 09, 2006, 12:10:12 AM »
The product tested was R-13 Ultratouch Blue cotton  insulation.

http://www.acousticalsurfaces.com/wall_insulation/pdf/acoustic_test/AS_TL1766.pdf

 

anything