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Strong-Drive® SDWF FLOOR-TO-FLOOR Screw 

Strong-Drive® SDWF FLOOR-TO-FLOOR Screw

New! Now Available in 30-Inch Length

The Strong-Drive SDWF Floor-to-Floor screw is designed to simplify the wind-uplift restraint connection while providing superior performance over the life of the structure. The unique design of the SDWF enables it to attach upper and lower walls together from the top, spanning the floor system and providing an easy-to-install connection within the continuous uplift load path of the structure.

The innovative Take-Up Washer (TUW) plays a key role in the long-term performance of the SDWF when installed between the screw head and the sole plate of the upper floor. As the structure settles because of shrinkage and construction loading, the threaded portion under the head of the screw ratchets up through the tabs of the TUW, which is fastened with Simpson Strong-Tie Strong-Drive SD screws. The interlock between the tabs of the take-up washer and the threads under the head of the SDWF prevent the screw from sliding back under load, providing a simple yet reliable means of shrinkage compensation up to 3/4" per story.

Key Features

  • Faster to install than other floor-to-floor connection methods — drive the screw, install the take-up washer and the connection is made from plate-to-plate
  • Shrinkage compensation ensures a tight connection even after initial shrinkage and settlement occur
  • Installs from inside the structure, eliminating exterior work on upper stories and enhancing job safety
  • Fastening can be done before or after exterior sheathing is applied for added flexibility
  • One screw length can be used for multiple floor depths (refer to chart to select appropriate screw size), reducing the need for many screw lengths

Applications

  • Wind-uplift restraint connections

Product Includes

Kit includes all required installation hardware:

  • (25) Strong-Drive SDWF Floor-to-Floor screws
  • (25) TUW take-up washers (washer is galvanized 10 ga. steel)
  • (100) Strong-Drive SD Connector screws (#9)
  • 5/16" hex driver bit (replacement driver bit — BITHEXR516-134)
  • Screw depth guide to ensure proper SDWF engagement with TUW

Related Literature

Product Information Table

Fastener Production Information and Stuff & Things
New products
Model No. Coating/Material Length (in.) Head Diameter (in.) Shank Diameter (in.) Drive Type Head Type Thread Type Thread Length Point Type Packaging Qty. UPC
SDWF2716-TUW E-coat® Electrocoating 16 0.730 0.270 5/16 in. Hex Hex Washer Head Variable Thread Design 5 Type-17 Point 25 707392478805
SDWF2720-TUW E-coat® Electrocoating 20 0.730 0.270 5/16 in. Hex Hex Washer Head Variable Thread Design 5 Type-17 Point 25 707392885405
SDWF2724-TUW E-coat® Electrocoating 24 0.730 0.270 5/16 in. Hex Hex Washer Head Variable Thread Design 5 Type-17 Point 25 707392845904
SDWF2726-TUW E-coat® Electrocoating 26 0.730 0.270 5/16 in. Hex Hex Washer Head Variable Thread Design 5 Type-17 Point 25 707392448709
SDWF2730-TUW E-coat® Electrocoating 30 0.730 0.270 5/16 in. Hex Hex Washer Head Variable Thread Design 5 Type-17 Point 25 707392455813

Product Information Table

Model No. Length (in.) Drive Type Head Diameter (in.) Head Type Thread Length Thread Type Shank Diameter (in.) Point Type Coating/Material Packaging Quantity UPC
SDWF2716-TUW 16 5/16 in. Hex 0.73 Hex Washer Head 5 Variable Thread Design 0.270 Type-17 Point E-Coat® Electrocoating 25 707392478805
SDWF2720-TUW 20 5/16 in. Hex 0.73 Hex Washer Head 5 Variable Thread Design 0.270 Type-17 Point E-Coat® Electrocoating 25 707392885405
SDWF2724-TUW 24 5/16 in. Hex 0.73 Hex Washer Head 5 Variable Thread Design 0.270 Type-17 Point E-Coat® Electrocoating 25 707392845904
SDWF2726-TUW 26 5/16 in. Hex 0.73 Hex Washer Head 5 Variable Thread Design 0.270 Type-17 Point E-Coat® Electrocoating 25 707392448709
SDWF2730-TUW 30 5/16 in. Hex 0.73 Hex Washer Head 5 Variable Thread Design 0.270 Type-17 Point E-Coat® Electrocoating 25 707392455813

Load Tables

Product Information and Withdrawal Loads
Model No. Size (in.) Thread Length (in.) Joist Depth Below (in.) Allowable Withdrawal per Thread Penetration (lb./in.)
Single Bottom Plate Double Bottom Plate
Min. Max. Min. Max. SP DF SPF
SDWF2716-TUW 0.27 x 16 5 8 1/2 10 1/2 6 7/8 9 295 250 180
SDWF2720-TUW 0.27 x 20 5 12 1/2 14 1/2 10 7/8 13
SDWF2724-TUW 0.27 x 24 5 16 1/2 18 1/2 14 7/8 17
SDWF2726-TUW 0.27 x 26 5 18 1/2 20 1/2 16 7/8 19
SDWF2730-TUW 0.27 x 30 5 22 1/2 24 1/2 20 7/8 23
  1. Allowable loads are for CD=1.0 and may be increased for load duration up to CD = 1.6.
  2. Joist depth listed based on the 3/4" subfloor and 3" of thread penetration into double top plates.

SDWF-TUW Floor-to-Floor Screw — On Center Spacing for Uniform Uplift Loads

  1. Spacing listed based on lesser of: single bottom plate bending allowable load, single bottom plate deflection limited to spacing/240 and 1/4" max, screw allowable withdrawal load, and take-up washer allowable load.
  2. Withdrawal load is based on a CD = 1.6 and minimum 3" penetration into lower wall double top plates.
  3. Stud-to-plate connections are required to complete the load path. These connections shall not exceed the lesser of 48" o.c. or SDWF spacing.
  4. Spacing values listed for SP lumber consider new base values adopted by AWC on June 1, 2012.
Concentrated Uplift Loads
Model No. Single SDWF-TUW Double SDWF-TUW
Allowable Tension Load (lb.) Deflection at Highest Allowable Load (in.) Allowable Tension Load (lb.) Deflection at Highest Allowable Load (in.)
SP DF SPF SP DF SPF
SDWF2716-TUW 1,410 1,200 865 0.095 2,270 2,125 1,730 0.142
SDWF2720-TUW
SDWF2724-TUW
SDWF2726-TUW
SDWF2730-TUW
  1. Allowable loads listed include a wood load duration factor of CD = 1.6 for wind or earthquake loading with no further increase allowed; reduce when other loads govern.
  2. Single and double SDWF-TUW applications listed are for concentrated load uplift restraint conditions (i.e. end of header, at girders, or at the end of shearwalls).

See additional Load Tables, Technical Data and Installation Instructions for the Strong-Drive® SDWF Floor-to-Floor screw.

 

Drawings

Part Orthographic Perspective
SDWF2716-TUW
SDWF Detail Sheet
DWGDXF
SDWF2716-TUW Front View
DWG DXF
SDWF2716-TUW Left View
DWG DXF
High Wind Resistant Construction Detail D134: Building Floor-to-Floor Straps - HWRC D134 Load Path Installation Considerations Building Floor to Floor Straps
DWG DXF
High Wind Resistant Construction Detail D149: Floor to Floor - HWRC D149 Floor to Floor Typical Strong Drive SDWF and TUW Installation
DWG DXF
High Wind Resistant Construction Detail D150: Floor to Floor - HWRC D150 Floor to Floor Typical SDWF FLOOR TO FLOOR Screw Angle Limit Installation
DWG DXF
High Wind Resistant Construction Detail D151: Floor to Floor - HWRC D151 Floor to Floor Double SDWF Cncntrtd Load Rstrnt Dtl at Cont Wall
DWG DXF
High Wind Resistant Construction Detail D152: Floor to Floor - HWRC D152 Floor to Floor Perspective view of Corner Conditions with Double SDWF
DWG DXF
SDWF2716-TUW Installed Perspective View Installed
DWG DXF
SDWF2716-TUW Perspective View
DWG DXF
High Wind Resistant Construction Detail D46: Stud to Stud - HWRC D46 Stud to Stud
DWG DXF
SDWF2720-TUW
SDWF Detail Sheet
DWGDXF
SDWF2716-TUW Front View
DWG DXF
SDWF2716-TUW Left View
DWG DXF
High Wind Resistant Construction Detail D134: Building Floor-to-Floor Straps - HWRC D134 Load Path Installation Considerations Building Floor to Floor Straps
DWG DXF
High Wind Resistant Construction Detail D149: Floor to Floor - HWRC D149 Floor to Floor Typical Strong Drive SDWF and TUW Installation
DWG DXF
High Wind Resistant Construction Detail D150: Floor to Floor - HWRC D150 Floor to Floor Typical SDWF FLOOR TO FLOOR Screw Angle Limit Installation
DWG DXF
High Wind Resistant Construction Detail D151: Floor to Floor - HWRC D151 Floor to Floor Double SDWF Cncntrtd Load Rstrnt Dtl at Cont Wall
DWG DXF
High Wind Resistant Construction Detail D152: Floor to Floor - HWRC D152 Floor to Floor Perspective view of Corner Conditions with Double SDWF
DWG DXF
SDWF2716-TUW Installed Perspective View Installed
DWG DXF
SDWF2716-TUW Perspective View
DWG DXF
High Wind Resistant Construction Detail D46: Stud to Stud - HWRC D46 Stud to Stud
DWG DXF
SDWF2724-TUW
SDWF Detail Sheet
DWGDXF
SDWF2716-TUW Front View
DWG DXF
SDWF2716-TUW Left View
DWG DXF
High Wind Resistant Construction Detail D134: Building Floor-to-Floor Straps - HWRC D134 Load Path Installation Considerations Building Floor to Floor Straps
DWG DXF
High Wind Resistant Construction Detail D149: Floor to Floor - HWRC D149 Floor to Floor Typical Strong Drive SDWF and TUW Installation
DWG DXF
High Wind Resistant Construction Detail D150: Floor to Floor - HWRC D150 Floor to Floor Typical SDWF FLOOR TO FLOOR Screw Angle Limit Installation
DWG DXF
High Wind Resistant Construction Detail D151: Floor to Floor - HWRC D151 Floor to Floor Double SDWF Cncntrtd Load Rstrnt Dtl at Cont Wall
DWG DXF
High Wind Resistant Construction Detail D152: Floor to Floor - HWRC D152 Floor to Floor Perspective view of Corner Conditions with Double SDWF
DWG DXF
SDWF2716-TUW Installed Perspective View Installed
DWG DXF
SDWF2716-TUW Perspective View
DWG DXF
High Wind Resistant Construction Detail D46: Stud to Stud - HWRC D46 Stud to Stud
DWG DXF
SDWF2726-TUW
SDWF Detail Sheet
DWGDXF
SDWF2716-TUW Front View
DWG DXF
SDWF2716-TUW Left View
DWG DXF
High Wind Resistant Construction Detail D134: Building Floor-to-Floor Straps - HWRC D134 Load Path Installation Considerations Building Floor to Floor Straps
DWG DXF
High Wind Resistant Construction Detail D149: Floor to Floor - HWRC D149 Floor to Floor Typical Strong Drive SDWF and TUW Installation
DWG DXF
High Wind Resistant Construction Detail D150: Floor to Floor - HWRC D150 Floor to Floor Typical SDWF FLOOR TO FLOOR Screw Angle Limit Installation
DWG DXF
High Wind Resistant Construction Detail D151: Floor to Floor - HWRC D151 Floor to Floor Double SDWF Cncntrtd Load Rstrnt Dtl at Cont Wall
DWG DXF
High Wind Resistant Construction Detail D152: Floor to Floor - HWRC D152 Floor to Floor Perspective view of Corner Conditions with Double SDWF
DWG DXF
SDWF2716-TUW Installed Perspective View Installed
DWG DXF
SDWF2716-TUW Perspective View
DWG DXF
High Wind Resistant Construction Detail D46: Stud to Stud - HWRC D46 Stud to Stud
DWG DXF
SDWF2730-TUW
SDWF Detail Sheet
DWGDXF
None
TUW38None None