The Simpson Strong-Drive SDWS Timber Screw with Double-Barrier Coating is a high-strength structural fastener engineered as a direct, code-compliant alternative to traditional lag screws and through-bolting in wood framing applications. With a 0.220 in. shank diameter, 4 in. length, and a SawTooth point, this black-coated washer-head screw drives fast and holds firm - making it a practical choice for contractors and do-it-yourselfers tackling wood-to-wood connections and crating work. Code listed in IAPMO UES ER-192, it meets IRC and IBC requirements for most common wood framing applications, and its Double-Barrier Coating delivers corrosion resistance equivalent to hot-dip galvanization for reliable performance in certain exterior and preservative-treated wood environments.

Key Features

• Double-Barrier Coating: provides corrosion resistance equivalent to hot-dip galvanization - suitable for certain exterior and preservative-treated wood applications where long-term durability matters
• SawTooth Point: ensures fast starts and reduces installation torque, eliminating the need for predrilling in most applications and speeding up workflow on the job site
• Washer Head Design (0.760 in. diameter): creates a large bearing area that distributes load effectively and provides a secure, flush-driving finish with reduced surface damage
• T40 6-Lobe Drive: delivers positive bit engagement for easier, more controlled driving and improved bit life - reducing cam-out and driver fatigue during repeated use
• 5 TPI Thread with 2-3/8 in. Thread Length: bold thread geometry grips wood fibers aggressively for superior holding power, making this a reliable high-strength fastening solution
• Code Listed in IAPMO UES ER-192: meets IRC and IBC requirements for most common wood framing applications, giving contractors the compliance assurance they need on regulated projects
• Black Finish: provides a clean, finished appearance that blends with common structural lumber and treated wood surfaces in visible framing applications

Why This Product

• Replaces traditional lag screws and through-bolting without sacrificing structural integrity - simplifying installations that would otherwise require more complex hardware and tooling setups
• The SawTooth point and low-torque design mean most installations require no predrilling, saving significant time on wood-to-wood framing and crating projects
• Double-Barrier Coating equivalent to hot-dip galvanization makes this screw a dependable option for exterior and preservative-treated lumber applications where corrosion resistance is critical
• Code listed under IAPMO UES ER-192 with IRC and IBC compliance gives builders and inspectors confidence on residential and commercial framing projects governed by current building codes

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/Finish: Double-Barrier Coating
• Color: Black
• Country of Origin: Taiwan

Available Pack Options

• SDWS22400DBB-R50: 50 Pk - includes one 6-lobe, T40 driver bit
• SDWS22400DBBMB: 250 Pk - includes one 6-lobe, T40 driver bit
• SDWS22400DBB: 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 self-start in wood without a pilot hole in the majority of common wood framing situations.

Is this screw suitable for use with pressure-treated lumber?

Yes. The Double-Barrier Coating provides corrosion resistance equivalent to hot-dip galvanization, making this screw suitable for certain exterior and preservative-treated wood applications. Refer to the IAPMO UES ER-192 evaluation report for full details on approved applications.

What drive bit is recommended for installing SDWS Timber Screws?

A T40 6-lobe driver bit is recommended and works best with a low-speed 1/2-in. drill. The 6-lobe T40 drive system is designed for positive engagement, easier driving, and improved bit life during installation.

What building codes does this screw comply with?

This screw is code listed in IAPMO UES ER-192 and meets IRC and IBC code requirements for most common wood framing applications, making it a compliant choice for both residential and commercial structural fastening work.