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Fire Resistance

One Hour Endurance
One Hour Endurance - Manufactured Housing
Two Hour Endurance
Fire Separation Wall Assembly

One Hour Endurance

Figure 1
  1. Topping - (optional) lightweight or proprietary topping.

  2. Sub-flooring - 5/8" tongue-and-groove plywood or oriented strand board (OSB).

  3. Structural members - Open Joist™ floor trusses from a minimum depth of 9-1/2" to a maximum depth of 16", installed up to 24" on-center, maximum load design according to manufacturer L/480 load tables, with structural-graded 4x2 chords per NLGA grading rules for Canadian Lumber or graded by an inspection bureau or agency approved by the United States Department of Commerce Board of Review of the American Lumber Standards Committee with chord sizes of 4x2. Structural members should bear the WHI certification mark.

  4. Bridging - continuous 2x4 lumber nailed to the bottom chord and sides of the diagonals with 3" long nails. (See Installation Details)

  5. Resilient Channel - Rigid steel furring channels (inverted hat-type) 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 S screw.

  6. Gypsum Board - 1 layer of 5/8" thick Type X. Long edges located between joists perpendicular to the resilient channels. Short edges staggered by 4 feet. 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 - (optional) for acoustic performance and/or thermal protection.

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

  Fire Endurance Assembly – One Hour - DWG / PDF


One Hour Endurance - Manufactured Housing

Figure 1Figure 2
  1. 9-1/4" or deeper Open Joist™ 3x2 #2 SPF flanges at 16" on center

  2. (2) 2x10 #2 SPF rim board

  3. (1) 2x4 #2 SPF – laid flat

  4. (2) 2x6 or deeper #2 SPF rim board

  5. 1-1/2" airspace

  6. 1-1/4" x 1-1/2" wood filler

  7. (2) Layers** – 5/8" Type C drywall. Using construction adhesive is optional between inner and outer layers of drywall.

  8. 2x6 or deeper #2 SPF ceiling joist at 16" on center

  9. Inner layer of drywall is attached to the joist with 1-5/8" long Coarse Thread bugle head drywall screws spaced 12" o/c Outer layer of drywall is attached to the joist through inner layer with 2-1/2" long Coarse Thread bugle head drywall screws spaced 12" o/c. (Offset outer layer screws by 6" to avoid hitting inner layer screws.)

  10. Optional bead of foam adhesive* – two-part polyurethane – Avg. 1" bead


  11. 2x4 #2 SPF strongback recommended


  12. Optional batt insulation – placed in between joist bay


  13. 23/32" tongue and groove rated decking attached to Open Joist with a 1/4" bead of construction adhesive and 6d nails spaced at 6 inches along the perimeter and 12 inches on center in the field.

ITW-TACC is the approved supplier of both the one- and two-part construction adhesive and polyurethanes used in testing.

* Optional two-part foam adhesive is the F2100 Series, which binds the drywall to the 2x6 ceiling joists.
** Optional one-part construction adhesive is the F6400 Series, which binds the two layers of drywall together.

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

thumb   Fire Endurance Assembly – One Hour Manufactured Housing- DWG 1 / DWG 2 / DWG 3 / PDF
     


Two Hour Endurance

Figure 2

  1. Topping – (optional) lightweight or proprietary topping.

  2. Sub flooring - minimum 5/8” tongue-and-groove sheathing.

  3. Structural members: Open Joist floor trusses from a minimum depth 9-1/2”, installed up to 24” on-center, with structural-graded 3x2 or 4x2 chords per NLGA grading rules for Canadian Lumber or graded by an inspection bureau of agency approved by the United States Department of Commerce Board of Review of the American Lumber Standards Committee with chord sizes of 3x2 and 4x2. Open Joist should bear the WHI certification mark.

  4. Bridging - continuous 2x4 lumber nailed to the bottom chord and the sides of the diagonals with 2” long nails. (See Installation Details). The Ceiling Membrane shall consist of three layers of 15.9-mm (5/8”) proprietary Type C gypsum board. Each sheet will be not less than 1.22-m (4’) wide. Acceptable products include, but are not limited to: Lafarge North America Firecheck C gypsum board, National Gypsum Gold Bond Fireshield C gypsum board, and Georgia Pacific (GP) Gypsum ToughRock Fire Guard C gypsum board.

  5. Resilient Channel - rigid steel furring channels (inverted hat-type) approximately 19-mm (3/4” deep) spaced not more than 405-mm (16”) o.c. These channels shall be oriented perpendicular to the joists and attached to each truss using 70-mm (1-1/2”) Type S or W screws.

    *If Open Joist members are installed at 16” o.c. or less, this resilient channel is optional.

  6. Gypsum board -
    Base Layer of Gypsum Board
    The base or uppermost layer of gypsum board shall be attached directly to the channels (or bottom chord). The long-edges of the gypsum board shall be oriented perpendicular to the trusses and with all end joints centered over the trusses. End joints must be staggered by at least two supports. The panels of gypsum board in the base layer shall be attached directly to the bottom of the trusses using Type S or Type W wallboard screws not less than 50-mm (2”) in length. The screws shall be spaced not more than 175-mm (7”) apart along each truss. Screws shall be kept at least 38-mm (1-1/2”) from the sides and 25-mm (1”) from the ends of each sheet.

    Second Layer of Gypsum Board
    All joints between sheets in the second or middle layer of gypsum board must be staggered from those in the base layer. Except for the ends of each sheet, the second layer of gypsum board shall be attached to trusses using Type S or Type W wallboard screws not less than 64-mm (2-1/2”) in length. The screws shall be spaced not more than 175-mm (7”) apart along each truss. Screws shall be kept at least 38-mm (1-1/2”) from the sides of each sheet. The ends of each sheet in the second layer of gypsum board shall be attached to the gypsum board in the uppermost layer using Type G wallboard screws not less than 38-mm (1-1/2”) long. These screws shall be spaced not more than 175-mm (7”) apart and will be kept at least 38-mm (1-1/2”) from the ends of each sheet.

    Resilient Channel
    Rigid steel furring channels (inverted hat-type) approximately 19-mm (3/4” deep) spaced not more than 406-mm (16”) o.c. shall be installed beneath the second layer of gypsum board. These channels shall be oriented perpendicular to the joists and attached to each truss using 70-mm (2-3/4”) Type S screws.

    Face Layer of Gypsum Board
    The face or lowermost layer of gypsum board shall be attached directly to the rigid steel furring channels. The long-edges of the gypsum board shall be oriented perpendicular to the furring channels and with all end joints centered over the channels. End joints must be staggered by at least two supports. The panels of gypsum board in the face layer shall be attached to the furring channels using Type S wallboard screws not less than 32-mm (1-1/4”) in length. The screws shall be spaced not more than 175-mm (7”) apart along each channel. Screws shall be kept at least 38-mm (1-1/2”) from the sides and 12-mm (1/2”) from the ends of each sheet.

    All joints between adjacent sheets of gypsum board in the face layer shall be taped and finished, and the heads of all screws used to attach that layer of gypsum board to the furring channels shall be treated (finished) as specified in ASTM C 840 Standard Specification for Application and Finishing of Gypsum Board and CAN/CSA A82.31-M91 Gypsum Board Application.

  7. Insulation - insulation material is optional.

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

  Fire Endurance Assembly – Two Hours - DWG / PDF

Fire Separation Wall Assembly

To download one of the details below, right-click or Ctrl-click on the link, then choose “Save Target As” or “Save”. To view a thumbnail image of the detail, roll your mouse over the download link.

  Fire Separation Wall Assembly No. 1 - DWG / PDF
Fire Separation Wall Assembly No. 2 - DWG / PDF
Fire Separation Wall Assembly No. 3 - DWG / PDF
Fire Separation Wall Assemblies Nos. 1 thru 3 - DWG / PDF
Fire Separation Wall Assembly No. 4 - DWG / PDF
Fire Separation Wall Assembly No. 5 - DWG / PDF
Fire Separation Wall Assembly No. 6 - DWG / PDF
Fire Separation Wall Assembly No. 7 - DWG / PDF
Fire Separation Wall Assemblies Nos. 4 thru 7 - DWG / PDF
Fire Separation Wall Assembly No. 8 - DWG / PDF
Fire Separation Wall Assembly No. 8a - DWG / PDF
Fire Separation Wall Assembly No. 9 - DWG / PDF
Fire Separation Wall Assembly No. 10 - DWG / PDF
Fire Separation Wall Assembly No. 11 - DWG / PDF
Fire Separation Wall Assemblies Nos. 9 thru 11 - DWG / PDF
Fire Separation Wall Assembly Notes - DWG / PDF