The Simpson Strong-Drive SDWS Timber Screw in 0.220" shank diameter x 4" length is a high-strength structural wood fastener engineered as a direct, code-compliant alternative to traditional lag screws and through-bolts. Designed by Simpson Strong-Tie for both professional contractors and dedicated do-it-yourselfers, this timber screw features a SawTooth point, large washer head, and a double-barrier coating that delivers corrosion resistance equivalent to hot-dip galvanization - making it a reliable choice for exterior framing, preservative-treated wood connections, and heavy wood-to-wood fastening. Code listed under IAPMO UES ER-192 and meeting IRC and IBC code requirements for most common wood framing applications, this tan-colored structural screw brings confidence to every installation.

Key Features

• SawTooth Point - enables fast starts and reduces installation torque, eliminating the need for predrilling in most applications and saving significant time on the job site.
• Washer Head with 0.760" Head Diameter - provides a large bearing area against the wood surface, distributing load effectively and reducing the chance of pull-through in structural connections.
• Double-Barrier Coating - delivers corrosion resistance equivalent to hot-dip galvanization, making this timber screw suitable for certain exterior applications and preservative-treated lumber environments as specified in the evaluation report.
• T40 6-Lobe Drive Type - provides positive bit engagement, reducing cam-out during driving and extending driver bit life for high-volume installations.
• 0.220" Shank Diameter with 5 TPI Thread - the coarse, bold thread design offers superior holding power in wood-to-wood connections without requiring the additional hardware associated with through-bolting.
• 2-3/8" Thread Length - engineered to maximize embedment in the receiving member, optimizing withdrawal strength for structural timber applications.
• Code Listed - IAPMO UES ER-192 - meets IRC and IBC requirements for most common wood framing applications, giving contractors the documentation needed for inspections and engineered projects.
• Tan Color - designed to blend with common preservative-treated and natural wood tones, providing a cleaner finished appearance on visible connections.

Why This Product

• Replaces lag screws and through-bolts without sacrificing strength - the SDWS Timber Screw is specifically designed as a high-strength alternative to traditional hardware, reducing installation steps and labor time on wood framing and crating projects.
• Built for exterior and treated-wood applications - the double-barrier coating provides corrosion resistance equivalent to hot-dip galvanization, making this screw one of the few fastener options appropriate for certain preservative-treated lumber contexts where corrosion is a long-term concern.
• No predrilling required in most applications - the SawTooth point bites into wood immediately, streamlining the fastening process for contractors and DIYers working on high-volume framing or wood-to-wood connections.
• Inspection-ready code compliance - listed under IAPMO UES ER-192 and meeting both IRC and IBC requirements, this screw supports permit and inspection approval for residential and commercial wood framing projects without the need for additional engineering documentation in most cases.

Specifications

• Brand: Simpson Strong-Tie
• Shank Diameter: 0.220 in.
• Length: 4 in.
• Head Diameter: 0.760 in.
• Head Type: Washer Head
• Drive Type: T40 6-Lobe
• Point Type: SawTooth Point
• Thread Length: 2 3/8 in.
• TPI: 5
• Coating: Double-Barrier Coating
• Finish: Double-Barrier Coating
• Color: Tan

Available Pack Options

• SDWS22400DB-R12: 12 Pk - includes one 6-lobe, T40 driver bit
• SDWS22400DB-R50: 50 Pk - includes one 6-lobe, T40 driver bit
• SDWS22400DBMB: 250 Pk - includes one 6-lobe, T40 driver bit
• SDWS22400DB: 600 Pk - includes two 6-lobe, T40 driver bits

Approved Applications

• Fastening Wood-to-Wood
• Crating

Install With

• SDWS screws install best with a low-speed 1/2-in. drill and 6-lobe, T40 driver bit (included)

Frequently Asked Questions

Does this screw require predrilling before installation?

In most applications, predrilling is not required. The SawTooth point is specifically designed to ensure fast starts and reduce installation torque, allowing the screw to drive directly into wood without a pilot hole in the majority of wood-to-wood fastening scenarios.

Is this timber screw suitable for use with preservative-treated lumber?

Yes, within the conditions described in the evaluation report. The double-barrier coating provides corrosion resistance equivalent to hot-dip galvanization, making the SDWS Timber Screw suitable for certain exterior and preservative-treated wood applications as detailed in IAPMO UES ER-192.

What code standards does this screw meet?

This screw is code listed under IAPMO UES ER-192 and meets IRC and IBC code requirements for most common wood framing applications, making it appropriate for both residential and commercial structural connections where code documentation is required.

What driver bit is recommended for installing these timber screws?

A T40 6-lobe driver bit is required. For best results, use a low-speed 1/2-in. drill paired with a 6-lobe T40 driver bit. The 6-lobe drive design provides positive engagement that makes the screw easy to drive and helps extend bit life during installation.