The Simpson HDQ8-SDS3 14-inch Galvanized Holdown is a heavy-duty shear wall connector engineered by Simpson to deliver high-load performance with minimal deflection. The unique seat design of the HDQ8 greatly minimizes deflection under load, making it a dependable choice for structural holdown applications. This connector employs Strong-Drive SDS Heavy-Duty Connector screws, which install easily, reduce fastener slip and provide a greater net section when compared to bolts. It may be installed either flush or raised off the mudsill without a reduction in load value, offering genuine flexibility across a range of framing conditions.

Key Features

• SDS screws included with every holdown - ensures proper fasteners are always used, eliminating guesswork and reducing the risk of installation errors on the job site.
• No stud bolts to countersink at openings - simplifies installation and saves time by removing a common and tedious step found with traditional holdown hardware.
• 14-inch height with 7-gauge steel construction - provides a robust, high-strength build suited to demanding structural and high-load shear wall applications.
• Zinc Galvanized G90 coating - delivers extra corrosion resistance, keeping the connector protected in moisture-prone or demanding environments over the long term.
• Flush or raised mudsill installation with no reduction in load value - gives installers the flexibility to adapt to site conditions without compromising structural performance.

Why This Product

• Engineered to minimize deflection under load - the unique seat design of the HDQ8 directly addresses one of the most critical performance factors in holdown connectors, helping maintain structural integrity where it matters most.
• Faster, screw-based installation - Strong-Drive SDS screws reduce fastener slip and install more easily than traditional bolts, cutting labor time and improving overall connection quality for structural framing crews.
• Included fasteners eliminate compatibility concerns - because the correct SDS screws ship with the holdown, contractors do not need to source separate hardware or risk using mismatched fasteners on critical connections.
• Versatile mudsill compatibility - the ability to install flush or raised off the mudsill without any penalty to load rating means this holdown adapts to varying field conditions without requiring a different product or a redesign.

Specifications

• Model Number: HDQ8-SDS3
• Height: 14 in.
• Material Gauge: 7-gauge steel
• Coating: Zinc Galvanized, G90
• Finish: Zinc Galvanized, G90
• Installation Hardware: 7/8 in. anchor bolt and 1/4 in. x 3 in. Strong-Drive SDS Heavy-Duty Connector screws (included)
• Width: 2-7/8 in.
• Seat Depth: 2-1/2 in.
• Centerline: 1-1/4 in.
• Screw Offset: 2-3/8 in.
• Country of Origin: United States

What's Included

Each pack contains (1) HDQ8-SDS3 Holdown, 1/4 in. x 3 in. Strong-Drive SDS Heavy-Duty Connector screws.

Downloads and Resources

• View Specifications

Frequently Asked Questions

What type of fasteners are used to install the HDQ8-SDS3?

The HDQ8-SDS3 installs with a 7/8 in. anchor bolt and 1/4 in. x 3 in. Strong-Drive SDS Heavy-Duty Connector screws, which are included with the holdown to ensure proper fasteners are used.

Can the HDQ8-SDS3 be installed raised off the mudsill?

Yes. The HDQ8-SDS3 may be installed either flush or raised off the mudsill without a reduction in load value, providing added installation flexibility.

What gauge steel is the HDQ8-SDS3 made from?

The HDQ8-SDS3 is made from 7-gauge steel, providing a robust, high-strength construction suitable for high-load applications.

What corrosion protection does the HDQ8-SDS3 provide?

The HDQ8-SDS3 features a Zinc Galvanized G90 coating, which provides extra corrosion resistance for use in demanding environments.