The Simpson Strong-Tie HD3B HDB 8-5/8 in. 12-Gauge Galvanized Bolted Holdown is engineered to provide reliable load performance for intermediate-load-range shearwalls, braced-wall panels, and lateral applications in wood construction. This bolted holdown installs with bolts into studs or columns, delivering low-deflection performance across a range of load requirements. The HD3B is especially well-suited for back-to-back applications where eccentricity is a concern, and its self-jigging design simplifies installation while ensuring code-required bolt spacing compliance.

Key Features

• Installed after the placement of concrete and framing is in place
• Can be installed directly on the sill plate or raised above it
• Self-jigging, ensuring the code-required minimum of seven bolt diameters from the end of the post when installed flush with the sill plate
• Light-duty holdown designed for use in shearwalls and braced-wall panels, as well as other lateral applications
• Suitable for back-to-back applications where eccentricity is a concern
• Offers low-deflection performance for a range of load requirements
• Made from 12-gauge steel
• Galvanized (G90) for corrosion resistance
• Made in the United States

Specifications

• MPN: HD3B
• Brand: Simpson Strong-Tie
• Gauge: 12
• Width: 2-1/2 in.
• Height: 8-5/8 in.
• Coating/Finish: Zinc Galvanized, G90
• Install With: 5/8 in. anchor bolt and 5/8 in. stud machine bolts
• Hole Bottom: 4-3/4 in.
• SB: 2-1/2 in.
• Seat Depth: 2-1/4 in.
• Centerline: 1-5/16 in.
• Screw Offset: 3/8 in.
• Country of Origin: United States

Approved Applications

• Intermediate-load-range shearwalls in wood construction
• Braced-wall panels requiring lateral load resistance
• General lateral applications in wood-framed structures
• Back-to-back holdown installations where eccentricity is a concern

Frequently Asked Questions

When during construction is the HD3B holdown installed?

The HD3B is installed after the placement of concrete and framing is in place. It can be installed directly on the sill plate or raised above it, providing flexibility depending on project requirements.

What fasteners are required to install the HD3B?

The HD3B is installed with a 5/8 in. anchor bolt and 5/8 in. stud machine bolts. Proper bolt hole sizing and snug tightening with standard cut washers are essential for correct installation.

What does the self-jigging feature of the HD3B mean for installation?

The self-jigging design ensures that the code-required minimum of seven bolt diameters from the end of the post is automatically achieved when the holdown is installed flush with the sill plate, reducing the risk of improper spacing and simplifying the installation process.

Is the HD3B suitable for back-to-back installations?

Yes. The HD3B is specifically designed to be suitable for back-to-back applications where eccentricity is a concern, making it a practical choice for paired holdown configurations in shearwall and lateral load applications.