The Simpson HD5B HDB 9-3/8 in. Galvanized (G90) Bolted Holdown by Simpson is engineered to deliver reliable, low-deflection performance for intermediate-load-range shearwalls, braced-wall panels, and lateral applications in wood construction. Installed with bolts directly into studs or columns, this holdown connector accommodates a range of structural load requirements and is specifically suited for back-to-back applications where eccentricity is a concern.

Key Features

• Installed after concrete placement and framing is in place - allows the holdown to be added at the appropriate construction stage without requiring advance rough-in, reducing the chance of installation conflicts.
• Can be installed directly on the sill plate or raised above it - gives contractors flexibility to accommodate varying framing conditions and anchor bolt projections on the job site.
• Self-jigging design - automatically positions the connector to maintain the code-required minimum of seven bolt diameters from the end of the post when installed flush with the sill plate, saving layout time and supporting code compliance.
• Unique seat design that greatly minimizes deflection under load - helps the structure perform more rigidly under lateral forces, which is critical for shearwall and braced-wall panel applications.
• Base made from 3/16-in. steel; body made from 10-gauge steel - combines a heavier base for bearing strength with a lighter body, balancing structural performance and material efficiency.
• G90 zinc galvanized coating - provides a durable corrosion-resistant finish suited for wood framing environments where long-term protection is required.

Why This Product

• Purpose-built for intermediate-load lateral connections - the HDB holdown is specifically designed for intermediate-load-range shearwalls and braced-wall panels, making it a well-matched choice when the load demand falls between light-duty straps and heavy-duty holdown hardware.
• Back-to-back compatible where eccentricity matters - the design is explicitly suited for back-to-back holdown installations, a common requirement in double-sided shearwall or post-column connections where misalignment of forces could compromise performance.
• Low-deflection performance built into the seat geometry - the unique seat design actively reduces movement under load rather than relying solely on material thickness, supporting tighter drift tolerances in lateral force-resisting systems.
• Flexible installation without sacrificing code compliance - the self-jigging feature and sill plate positioning options let installers adapt to field conditions while the connector itself maintains the geometry required for code-minimum bolt spacing.

Specifications

• Model Number: HD5B
• Width: 2-1/2 in.
• Height: 9-3/8 in.
• Gauge: 10
• Coating/Finish: Zinc Galvanized, G90
• Install With: 5/8 in. anchor bolt and 3/4 in. stud machine bolts
• Hole Bottom: 5-1/4 in.
• SB: 3 in.
• Seat Depth: 2-1/2 in.
• Centerline: 1-1/4 in.
• Screw Offset: 2 in.
• Country of Origin: United States

Approved Applications

• Intermediate-load-range shearwall holdown connections
• Braced-wall panel lateral applications in wood construction
• Back-to-back holdown installations where eccentricity must be minimized
• Connections into studs or columns requiring low-deflection performance

Frequently Asked Questions

What fasteners are required to install the HD5B holdown?

The HD5B is installed with a 5/8 in. anchor bolt for the concrete connection and 3/4 in. stud machine bolts for the wood framing connection.

Can the HD5B be installed directly on the sill plate?

Yes. The HD5B can be installed directly on the sill plate or raised above it, offering flexibility to suit different framing conditions. When installed flush with the sill plate, the self-jigging design ensures the code-required minimum of seven bolt diameters from the end of the post is maintained.

Is the HD5B suitable for back-to-back installations?

Yes. The HD5B HDB holdown is specifically suited for back-to-back applications where eccentricity is a concern, making it a practical choice for double-sided shearwall or column connections.

What is the corrosion-resistance rating of the HD5B, and what is it made from?

The HD5B features a Zinc Galvanized G90 coating for corrosion resistance. The base is made from 3/16-in. steel, while the body is constructed from 10-gauge steel, providing a robust combination of strength and durability.