Simpson 15-1/8" Heavy Holdown with Screws - Stainless Steel | HHDQ11SS-SDS2.5

The Simpson Strong-Tie HHDQ11SS-SDS2.5 is a 15-1/8-inch stainless steel heavy holdown engineered for extra-high load applications where strength, corrosion resistance, and installation efficiency are critical. Constructed from 7-gauge steel with a stainless steel finish, this holdown installs directly on the sill plate and is purpose-built to handle demanding structural connections with minimal fastener slip. Supplied complete with Strong-Drive SDS Heavy-Duty Connector screws, the HHDQ11SS-SDS2.5 eliminates guesswork by pairing the holdown with the correct fasteners right out of the box - ensuring code-compliant, high-performance installations every time.

Key Features

• Designed for extra-high loads - provides superior holding strength for demanding structural applications
• Strong-Drive SDS Heavy-Duty Connector screws included - ensures proper fasteners are always used, eliminating substitution errors
• Screws may be installed flush or raised off the mudsill - without any reduction in load value, offering greater installation flexibility
• No stud bolts to countersink at openings - simplifies installation and saves time on the job site
• Reduces fastener slip - Strong-Drive SDS screws provide a greater net section than traditional bolts
• Suitable for back-to-back applications - designed to address eccentricity concerns in paired holdown configurations
• Stainless steel finish - delivers enhanced corrosion resistance for demanding environments
• Installs directly on the sill plate - streamlined placement for efficient structural framing workflows
• Made in the United States - manufactured domestically to rigorous quality standards

Specifications

• Model Number: HHDQ11SS-SDS2.5
• Height: 15-1/8 in.
• Material: 7-gauge steel
• Finish: Stainless Steel
• Country of Origin: United States

Approved Applications

• Extra-high load holdown connections - ideal for high-demand shear wall and lateral force resisting system applications
• Sill plate installations - mounts directly to the sill plate for secure, low-profile placement
• Back-to-back holdown configurations - specifically suitable where eccentricity is a structural concern
• Corrosive environment framing - stainless steel finish makes this holdown appropriate for environments where standard steel finishes may be insufficient

What's Included

• 1x Simpson Strong-Tie HHDQ11SS-SDS2.5 Heavy Holdown (stainless steel)
• 1 in. anchor bolt
• 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws

Frequently Asked Questions

What fasteners are included with the HHDQ11SS-SDS2.5?

The HHDQ11SS-SDS2.5 comes supplied with Strong-Drive SDS Heavy-Duty Connector screws, ensuring the correct fasteners are paired with the holdown right out of the box and eliminating the risk of substitution errors on the job site.

Can the screws be installed raised off the mudsill without affecting load performance?

Yes. The Strong-Drive SDS screws included with this holdown may be installed either flush or raised off the mudsill without any reduction in load value, providing greater flexibility during installation.

Is this holdown suitable for back-to-back paired configurations?

Yes. The HHDQ11SS-SDS2.5 is designed to support back-to-back applications and is engineered to address eccentricity concerns that can arise in paired holdown configurations.

What material and gauge is the HHDQ11SS-SDS2.5 constructed from?

This holdown is constructed from 7-gauge steel with a stainless steel finish, providing enhanced corrosion resistance and making it well suited for applications where exposure to the elements or corrosive conditions is a concern.