The Simpson HDU4-SDS2.5 10-15/16 in. Predeflected Holdown is engineered by Simpson to deliver a rigid, reliable connection in wood-framed shearwalls, braced-wall panels, and other lateral-load applications. The body is pre-deflected during the manufacturing process, virtually eliminating deflection under load due to material stretch - giving builders a more stable holdown than conventional alternatives. Included Strong-Drive SDS Heavy-Duty Connector screws complete the package, making installation straightforward without the hassle of countersinking stud bolts at openings.

Key Features

• Predeflected body - virtually eliminates deflection due to material stretch under load, resulting in a more rigid, consistent connection over time
• Strong-Drive SDS Heavy-Duty Connector screws install easily - reduce fastener slip and provide a greater net section area of the post compared to bolts, improving overall connection integrity
• SDS screws supplied with the holdown - ensures the correct fasteners are always on hand, eliminating guesswork and reducing the risk of improper hardware substitution on the job site
• No stud bolts to countersink at openings - simplifies the installation process and saves time during framing
• 14-gauge steel construction - delivers structural strength suited to demanding holdown applications in wood framing
• Zinc Galvanized G90 finish - provides extra corrosion resistance, making this holdown suitable for use in environments where moisture exposure is a concern

Why This Product

• A more stable holdown from day one - because the body is pre-deflected at the factory, this holdown resists the material stretch that causes standard holdowns to shift or compress once load is applied, giving you a tighter, more predictable connection without field adjustments
• Faster installation with fewer steps - SDS screw-based fastening eliminates the need to countersink stud bolts at openings, cutting installation time and reducing labor complexity on wood-frame projects
• Everything needed arrives in the box - the included Strong-Drive SDS screws and crescent washer mean the right hardware is matched to the holdown from the start, removing uncertainty about fastener compatibility
• Built for long-term performance in real-world conditions - the G90 galvanized coating adds a layer of corrosion resistance that helps protect the connector in moisture-prone framing environments, extending the service life of the connection

Specifications

• MPN: HDU4-SDS2.5
• Height: 10-15/16 in.
• Gauge: 14
• Coating: Zinc Galvanized, G90
• Finish: Zinc Galvanized, G90
• Install With: Install with 5/8 in. anchor bolt and 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws (included)
• Country of Origin: United States

What's Included

Each pack contains (1) HDU4-SDS2.5 Predeflected Holdown, (10) 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws and (1) crescent washer.

Downloads and Resources

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Frequently Asked Questions

What does "predeflected" mean and why does it matter?

The HDU4-SDS2.5 holdown body is pre-deflected during the manufacturing process. This virtually eliminates deflection under load due to material stretch, resulting in a more rigid, stable connection compared to standard holdowns that can shift or compress once load is applied.

Why are SDS screws used instead of bolts in this holdown?

Strong-Drive SDS Heavy-Duty Connector screws install easily, reduce fastener slip, and provide a greater net section area of the post compared to bolts. They also eliminate the need to countersink stud bolts at openings, simplifying the installation process.

What fasteners are required to install the HDU4-SDS2.5?

Installation requires a 5/8 in. anchor bolt and 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws. The SDS screws are included with the holdown to ensure the correct fasteners are always used.

What material and corrosion protection does this holdown have?

The HDU4-SDS2.5 is made from 14-gauge steel with a Zinc Galvanized G90 coating and finish, providing extra corrosion resistance for long-term durability in demanding construction environments.

Note: Product dimensions and/or screw or bolt holes may differ from picture. Please see item description for specifications.