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Where speed meets strength.

Acoustical Performance

Figure 1

  1. Topping is Gypcrete or equivalent and/or carpet and pad (37 oz., 7/8" carpet with woven Polypropylene backing and 40 oz. felt pad or equivalent) or vinyl flooring (Armstrong Starstep or equivalent).
  2. Sub-flooring - Minimum 5/8" tongue and groove plywood or oriented strand board (OSB).
  3. Structural members - Open Joist™, all depths from 11-7/8" to and including 16", installed at 24" on-center or less.
  4. Bridging - (optional) Continuous 2x nailed to the bottom chord and sides of the diagonals or verticals with 2" long nails. (See Installation Details)
  5. Resilient Channel - Galvanized steel, 24 gauge, spaced 16" on-center and attached to the bottom chord by means of two (2) Type W screws. Channels overlap 10" at the end and are attached to each other by a 1-1/4" Type W screw.
  6. Gypsum Board - 1 layer of 5/8" Type X. Long edges located between joists perpendicular to the resilient channels. Short edges staggered by 4' . Sheets are fastened to the resilient channels by means of 1-1/2" Type S screws, located 1-1/2" away from the edge and 3" away from the long edge. Screws are spaced 6" on-center. Joints are taped and finished with two layers of compound.
  7. Insulation material - Cellulose (5-1/2" thick with 1.6 pcf density) or equivalent.

To download the Acoustical Performance Assembly detail below, right-click or Ctrl-click on the link, then choose “Save Target As” or “Save”.

  Acoustical Performance Assembly - DWG / PDF

 

Acoustical Characteristics Table

The table shows the acoustical performance of this assembly.
Joist Depth Insulation Gypcrete Carpet Vinyl STC IIC
9 1/4" Yes No No No 42 38
9 1/4" Yes No Yes No 42 66
9 1/4" Yes No No Yes 42 44
9 1/4" Yes Yes No No 44 42
9 1/4" Yes Yes Yes No 44 70
9 1/4" Yes Yes No Yes 44 50
9 1/4" No No No No 41 35
9 1/4" No No Yes No 41 63
9 1/4" No No No Yes 41 41
9 1/4" No Yes No No 44 32
9 1/4" No Yes Yes No 44 60
9 1/4" No Yes No Yes 44 38
             
11-7/8" Yes No No No 46 39
11-7/8" Yes No Yes No 46 67
11-7/8" Yes No No Yes 46 45
11-7/8" Yes Yes No No 53 44
11-7/8" Yes Yes Yes No 53 72
11-7/8" Yes Yes No Yes 53 50
11-7/8" No No No No 46 30
11-7/8" No No Yes No 46 65
11-7/8" No No No Yes 46 43
11-7/8" No Yes No No 52 37
11-7/8" No Yes Yes No 52 67
11-7/8" No Yes No Yes 52 43
             
14" Yes No No No 47 40
14" Yes No Yes No 47 68
14" Yes No No Yes 47 46
14" Yes Yes No No 53 44
14" Yes Yes Yes No 53 72
14" Yes Yes No Yes 53 50
14" No No No No 46 30
14" No No Yes No 46 65
14" No No No Yes 46 43
14" No Yes No No 52 37
14" No Yes Yes No 52 67
14" No Yes No Yes 52 43
             
16" Yes No No No 48 41
16" Yes No Yes No 48 69
16" Yes No No Yes 48 47
16" Yes Yes No No 53 45
16" Yes Yes Yes No 53 73
16" Yes Yes No Yes 53 51
16" No No No No 47 31
16" No No Yes No 47 65
16" No No No Yes 47 43
16" No Yes No No 53 38
16" No Yes Yes No 53 68
16" No Yes No Yes 53 44


Note: The values in Italic are estimated and represent the minimum expected value obtained through laboratory testing.

To download the Acoustical Characteristics table above, right click or ctrl-click on the link, then choose "Save Target As" or "Save".

  Acoustical Characteristics Table – PDF
Universal Forest Products Eastern Division, Inc. manufactures the Open Joist™ product as a licensee of Distribution Open Joist 2000, Inc.  All Open Joist product design and engineering calculations are created by the licensor, Distribution Open Joist 2000, Inc.