Key Features

Made for Shearwalls This holdown is built for shearwalls, braced-wall panels, and other lateral wood construction connections where uplift resistance matters. It gives you a dedicated tie point between the wood member and anchor bolt instead of relying on improvised hardware. SDS Screws Included The Simpson Strong-Tie HDU2-SDS2.5 holdown comes with the specified Strong-Drive SDS Heavy-Duty Connector screws and a crescent washer. That saves guesswork and helps make sure the connection is installed with the fasteners it was designed around. Predeflected Seat The predeflected seat is there to reduce deflection under load. In practical terms, that means a tighter, more predictable connection when the assembly is asked to do real structural work.

Overview

The Simpson Strong-Tie HDU2-SDS2.5 holdown is a galvanized steel holdown for wood construction. This is a holdown designed for shearwalls, braced-wall panels, and other lateral load connections. Model Number: HDU2-SDS2.5. If you are tying a post or wood member down to resist uplift and overturning forces, this is the kind of connector you spec when the connection needs to be intentional, repeatable, and built around known fasteners.

What makes this version different from a basic holdown is that Simpson includes the Strong-Drive SDS Heavy-Duty Connector screws with the part. That matters because structural connectors only perform the way they are supposed to when the right fasteners are used. Instead of chasing down separate hardware or mixing in whatever is on the truck, you get the specified screw package and crescent washer right with the connector.

The HDU series is designed for use in shearwalls and braced-wall panels, and the HDU2-SDS2.5 is one of the more compact models in that family. For this specific model, the body is made from 14-gauge steel, measures 3 inches wide, and has an overall height of 8-11/16 inches. That size makes it practical for tighter wall framing layouts while still giving you a dedicated heavy-duty tie-down point at the base of the member.

One of the more useful design details here is the predeflected seat. That feature is meant to eliminate deflection under load, which helps the connection engage more directly when the assembly is loaded. It is a small detail on paper, but in structural hardware, controlling movement at the connection is exactly the kind of thing that separates purpose-built hardware from a field workaround.

Another practical advantage is that there are no stud bolts to countersink at openings. On the job, that can simplify layout and reduce the extra fiddling that comes with bolt-based hardware in tight framing areas. Simpson also notes that the HDU requires no additional washer, which keeps the installed hardware stack straightforward.

The finish on this model is zinc galvanized G90. That gives it corrosion protection appropriate to the listed finish, and it is the standard finish for the non-HDG version of this connector. If your application calls for a different corrosion level, Simpson does offer additional corrosion-protection versions elsewhere in the HDU line, but this exact SKU is the zinc galvanized model.

Installation is built around a 5/8 inch anchor bolt and 1/4 inch x 2-1/2 inch Strong-Drive SDS Heavy-Duty Connector screws, with the screws included. Simpson also notes that these screws install best with a low-speed, high-torque drill using a 3/8 inch hex-head driver. That is the kind of detail that helps on install day because it tells you what setup works best instead of leaving it to trial and error.

This holdown makes the most sense for framers, builders, remodelers, and engineers working on code-driven wood framing connections where uplift resistance is part of the design. If you need a compact, specified wood-to-wood holdown with included structural screws and a predeflected seat, the HDU2-SDS2.5 is a straightforward choice. It is not general-purpose hardware. It is structural connection hardware meant to be installed as part of a designed load path.

See How the Connection Is Used

This is the real job the connector is built for: tying a wood member down at the base so uplift forces transfer into the anchor system and foundation. It is a structural connector meant to be part of the load path, not just a piece of bent metal.

• Designed for shearwalls, braced-wall panels, and other lateral applications
• Uses a 5/8 inch anchor bolt and included 1/4 inch x 2-1/2 inch SDS connector screws

Compact Size, Purpose-Built Layout

The HDU2-SDS2.5 is sized to do structural work without taking over the whole framing bay. Its geometry gives you a dedicated anchor seat at the base and a screw pattern up the post or stud face where the connector can do its job.

• Overall height: 8-11/16 in.
• Width: 3 in. and seat dimension B: 3-1/4 in.

What’s in the Box

• (1) Simpson Strong-Tie HDU2-SDS2.5 holdown
• (6) 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws
• (1) crescent washer

Key Specifications

Compatibility

Fastener System Designed to use 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws. The required screws are included. Anchor Interface Install with a 5/8 in. anchor bolt. Driver Setup SDS connector screws install best with a low-speed, high-torque drill equipped with a 3/8 in. hex-head driver.

Built For

Wood Framing Shearwalls Braced-Wall Panels High-Wind Construction General Contracting Remodeling

Pro Tip

Use a low-speed, high-torque drill with a 3/8 inch hex-head driver for the included SDS screws. It gives you better control seating the connector screws than a fast driver, especially when you are trying to keep the connection tight and clean.

At a Glance

14 ga Steel Body 8-11/16 in. Overall Height 6 Included SDS Screws 5/8 in. Anchor Bolt Size

Tool Nut’s Take

Tool Nut’s Take

Simpson Strong-Tie HDU2-SDS2.5 Holdown for Clean, Specified Tie-Down Work

This is a no-nonsense structural connector for builders who want the right holdown, the right screws, and less messing around at install time.

• Who it’s for: Framers, builders, and remodelers working on engineered wood framing, shearwalls, or braced-wall panels.
• Why it stands out: The included SDS connector screws, predeflected seat, and compact HDU2 size make it a practical option when you want a purpose-built uplift connection instead of piecing hardware together.
• Worth knowing: This is structural hardware, so it needs to be installed with the specified fasteners and anchor bolt size. Great part, but only when it is used the way the connection was designed.

Common Questions

• What is this connector designed for? It is designed for use in shearwalls, braced-wall panels, and other lateral applications in wood construction.
• Does this holdown include the required screws? Yes. This model includes (6) 1/4 in. x 2-1/2 in. Strong-Drive SDS Heavy-Duty Connector screws and (1) crescent washer.
• What anchor bolt size does it use? Simpson lists installation with a 5/8 in. anchor bolt for this model.
• What finish does this SKU have? The HDU2-SDS2.5 uses a zinc galvanized G90 finish.