Strong-Drive® SDWF FLOOR-TO-FLOOR Screw
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Product Details
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
Codes
- ICC-ES ESR-3046 (SDWF)
- ICC-ES ESR-2320 (TUW)
- State of Florida FL9589
- State of Florida FL10007 (TUW)
- City of Los Angeles RR25907
- U.S. Patent 8,276,323
Related Links
- Fastening Systems Technical and Installation Notes
- Installation Detail Drawings
- Recorded Webinar Drive a New Path: Resisting Uplift with Structural Fasteners
Catalog Pages
- Product Information: C-F-2017 (Fastening Systems), page 95
- Technical Data and Loads: C-F-2017 (Fastening Systems), pages 352–355
Related Literature
Product Information Table
| 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
| 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 | |||
|
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SDWF-TUW Floor-to-Floor Screw — On Center Spacing for Uniform Uplift Loads
- 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.
- Withdrawal load is based on a CD = 1.6 and minimum 3" penetration into lower wall double top plates.
- 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.
- Spacing values listed for SP lumber consider new base values adopted by AWC on June 1, 2012.
| 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 | ||||||||
|
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See additional Load Tables, Technical Data and Installation Instructions for the Strong-Drive® SDWF Floor-to-Floor screw.
Drawings
| Part | Orthographic | Perspective |
|---|---|---|
| SDWF2716-TUW |
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
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| SDWF2720-TUW |
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
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| SDWF2724-TUW |
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
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| SDWF2726-TUW |
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
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| SDWF2730-TUW | None | |
| TUW38 | None | None |
