SDI Recognized #12 Screws with PLB-36 Roof Deck

Perpendicular Supports

When Verco’s PLB-36 deck is to be screw fastened to supports, it shall be with minimum SDI Recognized (Buildex, ELCO, Hilti or Simpson Strong-Tie) #12 self-drilling, self-tapping screws with hex washer heads. The diaphragm shear and flexibility values shown in Verco’s evaluation report and on pages 44-47 of VR3 (Link Dead) assume minimum 54 mil (16 gage, or 0.0566 in.) cold-formed steel supports with minimum Fy = 33 ksi (Fu = 45 ksi). These shear and flexibility values may be modified for supports with different thickness and/or material strength using the adjustment factors shown in the evaluation report and catalog.

See the table below for suggested screw selection based on actual substrate thickness.

Suggested Screw Selection

Substrate Thickness

  • 33 mil (0.0346″) to 3/16″
  • 1/8″ to 1/4″
  • 1/4″ to 1/2″

Fastener Designation

  • #3 Drill Point
  • #4 Drill Point
  • #5 Drill Point

Parallel Supports

The spacing of screws at collectors or drags parallel to the deck ribs should be based on the shear force to be transferred. Allowable shear strengths for #12 screws with various gage decks can be found in Verco’s evaluation report and catalog.

See Verco Diaphragm Shear Tables with #12 Screws for PLB-36 Deck – Link Dead

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