The Simpson HDUE17-SDS4.5HDG HDUE 27-7/8 in. Hot-Dip Galvanized Predeflected Holdown with Strong-Drive SDS Screws is a heavy-duty structural connector engineered to deliver exceptional overturning resistance in residential wood construction. Designed specifically for securing shearwalls, braced wall panels, and other lateral-force-resisting systems, this holdown combines a predeflected seat, an overlapping back plate, and angled fastening technology to reduce deflection, minimize post splitting, and maximize load capacity. Built from 10-gauge steel with a hot-dip galvanized finish, it is well suited for exterior applications and use with pressure-treated lumber where corrosion resistance is critical. Installation is fast and efficient using the included Simpson Strong-Drive SDS Heavy-Duty Connector screws, making this holdown a reliable solution for modern structural demands.

Key Features

• Predeflected seat - reduces deflection under load, improving the stiffness and performance of the lateral-force-resisting system over time
• Angled fastening engages screws in tension - delivers higher load capacity per fastener, so fewer screws are needed to achieve required design loads
• Angled fastening tabs drive fasteners at a 45 deg. angle - offset holes on the second back plate prevent straight driving, ensuring every screw is optimally positioned for maximum engagement
• Overlapping back plate - increases fastener strength and shear values while helping prevent post splitting, protecting the structural integrity of the wood post
• Optimized screw patterns - reduce splitting at the end of the post and maximize individual fastener capacity, extending the service life of the connection
• Extruded seat adds greater cross-sectional steel section - provides added strength at the bearing point where loads are highest
• Teardrop holes - allow higher and more even distribution of load across the connector, reducing stress concentrations
• 10-gauge steel construction with hot-dip galvanization (HDG) - delivers extra corrosion resistance for exterior installations and connections to treated lumber, outperforming standard zinc coatings in aggressive environments
• 27-7/8 in. height - accommodates the tall post connections required in demanding residential shearwall applications
• Made in the United States - consistent manufacturing quality from a trusted structural connector brand

Why This Product

• The predeflected seat and angled fastening system work together to reduce deflection under lateral loads while requiring fewer screws - saving installation time without compromising structural performance in shearwall assemblies.
• Hot-dip galvanized steel construction provides a robust barrier against corrosion, making this holdown appropriate for exterior framing conditions and connections to pressure-treated wood where standard coatings may fail prematurely.
• The overlapping back plate and optimized screw patterns address one of the most common failure modes in holdown connections - post splitting - giving builders confidence that the connection will perform as designed throughout the life of the structure.
• All required Strong-Drive SDS Heavy-Duty Connector screws are included in the box, eliminating the need for a separate fastener order and ensuring the correct fasteners are always used with this connector.

Specifications

• Brand: Simpson Strong-Tie
• MPN: HDUE17-SDS4.5HDG
• Height: 27-7/8 in.
• Gauge: 10
• Coating: Hot-Dip Galvanized
• Finish: Hot-Dip Galvanized
• Color: None
• Packaging Quantity: 1
• Country of Origin: United States

What's Included

• (28) 1/4 in. x 4-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws and (1) crescent washer

Install With

• Install with 1 in. anchor bolt and (28) 1/4 in. x 4-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws (included)

Frequently Asked Questions

What makes the HDUE17-SDS4.5HDG different from a standard holdown?

The HDUE17-SDS4.5HDG features a predeflected seat that reduces deflection under load, an overlapping back plate that increases fastener strength and shear values, and angled fastening tabs that drive screws at a 45 deg. angle for higher per-screw load capacity. These design elements combine to deliver superior performance in shearwall, braced wall panel, and other lateral-force-resisting applications compared to conventional holdown designs.

Is this holdown suitable for use with pressure-treated lumber or in exterior applications?

Yes. The HDUE17-SDS4.5HDG is made from 10-gauge steel with a hot-dip galvanized (HDG) finish, which provides extra corrosion resistance specifically suited for exterior conditions and connections to pressure-treated wood. HDG coating offers a higher level of protection than standard zinc coatings in corrosive environments.

Are fasteners included, and what type of screws does this holdown use?

Yes. Each unit includes (28) 1/4 in. x 4-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws and (1) crescent washer. Installation also requires a 1 in. anchor bolt, which is not included. The SDS screws are driven at a 45 deg. angle using the holdown's angled fastening tabs, engaging the fasteners in tension for higher load capacity.

How does the teardrop hole design benefit the connection?

The teardrop-shaped holes in the HDUE17-SDS4.5HDG allow for higher and more even distribution of load across the connector. This reduces stress concentrations at individual fastener points, contributing to a more consistent and reliable connection throughout the life of the shearwall assembly.

Note: Product dimensions and/or screw or bolt holes may differ from picture.