Simpson Strong-Drive SDWH Timber-Hex Hot-Dip Galvanized Screw - 0.276 in. x 10 in. is a heavy-duty structural fastener engineered specifically for marine and coastal environments where corrosion resistance and installation speed are critical. Built by Simpson with a Hot-Dip Galvanized Class C coating, this 10-inch timber screw delivers the protection required for structural pilings, docks, piers, boardwalks, and other demanding waterfront applications. The large hex washer head, serrated threads, and SawTooth point work together to provide a fast, secure connection in heavy timber and engineered wood without the need for predrilling or separate hardware assemblies.

Key Features

• Hot-Dip Galvanized Class C Coating - provides a thick, durable zinc layer that resists corrosion in marine, coastal, and wet environments where standard fasteners would fail prematurely
• 0.276 in. Shank Diameter with 10 in. Length - delivers substantial structural holding power in deep timber connections, replacing the need for traditional bolt-washer-nut assemblies in many pile applications
• SawTooth Point - cuts aggressively into wood fiber for fast penetration without predrilling, reducing installation time and eliminating the cost of specialty auger drill bits
• Serrated Threads with 5 TPI - coarse thread pattern grips heavy timber and engineered wood firmly, resisting pull-out forces in structural connections such as ledger and pile installations
• 3-inch Thread Length - concentrates engagement at the critical pull-through zone, maximizing holding strength in the connected member
• Large Hex Washer Head (0.930 in. Diameter) with 3/8 in. Hex Drive - the oversized integral washer head distributes load across a wide bearing surface while the hex drive allows high torque installation with a standard corded drill - no separate washer needed
• Single-Sided Installation - installs entirely from one side of the connection, eliminating the need for a second worker or access to the back of the assembly, which significantly lowers labor costs on dock and pier projects

Why This Product

• For structural pilings, docks, and marine boardwalks, the Hot-Dip Galvanized Class C coating provides the corrosion protection demanded in saltwater and coastal conditions - where lesser coatings break down and compromise structural integrity over time
• No predrilling required and no separate washers, nuts, or bolts to manage - this screw eliminates multiple hardware components and installation steps, reducing both material cost and time on pile and heavy timber jobs
• One-sided installation makes it practical for tight, awkward, or elevated structural situations common on piers and boardwalks where reaching both sides of a connection is difficult or impossible
• The combination of SawTooth point, serrated threads, and large hex washer head delivers a self-contained structural fastener solution that can replace traditional bolt assemblies in many pile connection scenarios, lowering the overall installed cost

Specifications

• Brand: Simpson Strong-Tie
• Shank Diameter (in.): 0.276
• Length (in.): 10
• Coating: Hot-Dip Galvanized, Class C
• Head Type: Large Hex Washer Head
• Head Diameter (in.): 0.930
• Drive Type: 3/8 in. Hex
• Thread Type: Serrated Threads
• Thread Length (in.): 3
• TPI: 5
• Point Type: SawTooth Point

Available Pack Options

• SDWH271000G-RP1: 1 Ea
• SDWH271000GR30: 30 Pk - includes (1) driver bit
• SDWH271000GMB: 150 Pk - includes (2) driver bits

Approved Applications

• Structural pilings and pile connections
• Piers and docks in marine and coastal environments
• Boardwalks and heavy timber decking structures
• Structural wood-to-wood connections including ledgers
• Engineered wood structural connections

Install With

• For best results, use a minimum of 1/2 in. low-speed corded drill to install

Frequently Asked Questions

Does this screw require predrilling before installation?

No predrilling is required. The SawTooth point is designed to penetrate heavy timber and engineered wood directly, allowing the screw to be driven without pilot holes or specialty auger drill bits, saving time and reducing tool costs on the job site.

What type of coating does this screw have, and is it suitable for saltwater or coastal use?

This screw features a Hot-Dip Galvanized Class C coating, which is specifically suited for heavy-duty marine and coastal applications including structural pilings, piers, docks, and boardwalks where exposure to moisture, salt, and corrosive conditions is expected.

What tool is recommended for driving this screw?

For best results, use a minimum of a 1/2 in. low-speed corded drill with a 3/8 in. hex bit. The large hex washer head accepts high installation torque, which is important for driving a 10-inch fastener fully into heavy structural timber.

Can this screw replace traditional bolt-washer-nut assemblies in pile connections?

Yes. This screw is designed to replace 3/4 in. and 5/8 in. HDG bolt, washer, and nut assemblies in many pile connection conditions, eliminating the need to purchase separate washers, nuts, or bolts and enabling single-sided installation that reduces labor time significantly.