Simpson Strong-Tie Strong-Drive SDWC TRUSS Screw, .155-in. x 4-1/2-in. T-30 6-Lobe E-coat, Black, 500-Pack (SDWC15450B-KT)

Key Features

Full-Thread Hold The fully threaded shank grabs along the screw’s working length, helping lock trusses, rafters, and studs tight to plates instead of relying on a short threaded section. Inside-Install Advantage This truss screw can be installed from inside the structure, which helps cut down ladder and exterior work on upper walls and keeps framing moving when access is tight. Flush Cap Head The cap-style head countersinks into the double top plate so it stays out of the way of drywall and finish work later in the job.

Overview

Simpson Strong-Tie SDWC15450B-KT Strong-Drive SDWC Truss Screw is a structural wood screw built for truss or rafter-to-plate and stud-to-plate connections in framing work. This is a structural wood screw designed for fastening roof and wall framing members in high-wind construction and other code-driven wood framing applications. Model Number: SDWC15450B-KT. If you want a fastener that gives you a strong connection without needing exterior access, this is the one this product was made for.

The big deal here is the fully threaded shank. On the job, that matters because the threads engage through the connection instead of only biting near the tip. That helps pull framing members together and keep them there. For truss and rafter work, that means a more secure roof-to-wall tie. For stud-to-plate fastening, it gives you a purpose-built alternative for connections where holding power and installation angle matter.

Simpson designed this screw around real framing workflow, not just lab numbers. The cap head is made to countersink into the double top plate so the head does not stand proud and get in the way of drywall crews or finish work. The wide tolerance on installation angle also helps when you are driving overhead or working in cramped stud bays where perfect drill positioning is not realistic.

The Type-17 point is there for a reason. It starts faster, cuts into wood more cleanly, and makes driving easier, especially when you are repeating the same connection over and over. Paired with the T30 6-lobe drive, you get solid bit engagement with less cam-out than a weaker drive style. That usually means less stripped heads, steadier driving, and better bit life when you are running a lot of screws in a day.

For jobsite practicality, this screw can be installed before or after exterior sheathing is applied. That gives framers flexibility depending on sequencing, crew size, and site access. Just as important, it can be installed from inside the structure, which is one of the main reasons contractors buy this style in the first place. Less exterior access work means less time on ladders or staging and an easier path on multi-story framing.

This specific SDWC15450B-KT version is the black E-coat model in the 4-1/2 inch length, packaged in a 500-count bucket-style kit. It uses a cap head, a T30 6-lobe drive, and a 4-1/4 inch thread length. The included metal installation guide tools help keep the screw at the proper angle, which is important because the connection performance depends on correct installation, not just the screw itself.

Material and finish matter with structural fasteners, too. This model uses steel construction with E-coat electrocoating and is recognized for use in chemically treated wood as described in the evaluation report referenced by Simpson Strong-Tie. If you are working in framing conditions where corrosion resistance and approved use matter, that is not filler spec talk. That is the kind of detail that helps you choose the right fastener before inspection, not after.

Who should buy it? Framers, builders, remodelers, and general contractors doing roof framing, wall framing, and high-wind connection work. It is also a good fit for crews that want a code-oriented fastening method that installs from the inside and keeps the head flush in the plate. If you are just looking for a generic wood screw, this is overkill. If you are doing truss fastening and plate connections the right way, this is exactly the kind of screw you buy on purpose.

Install From Inside the Structure

This fastening approach is built around real framing access. Instead of depending on exterior positioning, the SDWC system lets you drive the connection from inside the wall line, which helps on tall walls, awkward roof lines, and fast-paced framing schedules.

• Designed for truss or rafter-to-plate and stud-to-plate connections
• Can be installed before or after exterior sheathing is applied
• Useful for high-wind construction where connection details matter

Guide the Angle, Drive It Clean

The included metal guide tool is not throw-in hardware. It helps you keep the installation angle consistent, which is a big part of getting the connection right when you are driving repeatedly in plates and studs.

• (2) metal installation guide tools are included
• T30 6-lobe drive provides positive bit engagement
• Wide installation-angle tolerance helps overhead and in-bay driving

Built as a Structural Fastener, Not a General Screw

What separates this from a standard wood screw is the connection-focused design. The full thread, cap head, and Type-17 point all work together to make repetitive framing fastening faster and more consistent.

• 4-1/2 in. overall length with 4-1/4 in. thread length
• Cap head countersinks into the double top plate
• Type-17 point helps with faster starts and easier driving

What’s in the Box

• (500) Simpson Strong-Tie SDWC15450B-KT Strong-Drive SDWC Truss Screws
• (2) T30 driver bits
• (2) metal installation guide tools

Key Specifications

Compatibility

Drive Interface Uses a T30 6-lobe driver bit for installation. Replacement Bit Replacement driver bit listed by Simpson Strong-Tie: BIT30T-2-R2. Wood Use Recognized for use in chemically treated wood as described in the evaluation report.

Built For

Roof Framing Wall Framing Truss-to-Plate Connections Rafter-to-Plate Connections Stud-to-Plate Connections High-Wind Construction Carpentry General Contracting

Pro Tip

Use the included metal guide tool when you start your run, especially overhead. It keeps your angle consistent, which makes the screw drive cleaner and helps you avoid rework on connections that need to pass inspection.

Warranty & Support

Warranty listed in supplementary product data: 12 months.

Tool Nut’s Take

Tool Nut’s Take

Simpson Strong-Tie SDWC15450B-KT Strong-Drive SDWC Truss Screw gets the framing detail right

This is the kind of structural screw that earns its keep by making a specific connection faster, cleaner, and easier to install correctly.

• Who it’s for: Framers, remodelers, and builders doing truss, rafter, and stud-to-plate fastening where proper connection hardware matters.
• Why it stands out: Full-thread holding power, a flush cap head, inside-the-structure installation, and guide tools in the box all make this more job-ready than a generic structural screw.
• Worth knowing: This is a purpose-built 4-1/2 in. black E-coat framing fastener in a 500-pack, so it makes the most sense when you are doing repeat structural connections, not one-off shop work.

Common Questions

• What is this screw designed for? It is designed for truss or rafter-to-plate and stud-to-plate connections in wood framing.
• Can it be installed from inside the building? Yes. One of the key benefits of the SDWC design is that installation can be done from inside the structure.
• Can fastening be done before or after exterior sheathing? Yes. Simpson states fastening can be performed before or after exterior sheathing is applied.
• What bit does it use? It uses a T30 6-lobe driver bit.
• Is it approved for treated wood use? Simpson states the SDWC15450 is recognized for use in chemically treated wood as described in the evaluation report.