The Simpson ABU ZMAX Galvanized Adjustable Standoff Post Base for 5-1/8 in. x 5-1/8 in. Engineered Lumber by Simpson Strong-Tie is built to securely attach wooden posts to existing concrete in high-capacity structural applications. The slotted base and built-in standoff design combine adjustability with code-compliant moisture protection, while ZMAX galvanization delivers durable corrosion resistance for exterior and treated-wood installations. Whether the application involves earthquake loading, wind uplift, or exposure to weather and water splash, this post base is engineered to perform where structural reliability matters most.

Key Features

• Slotted anchor hole in the base - allows flexibility around the anchor bolt so precise post placement is easier, reducing installation frustration even when anchor positions are not perfectly centered.
• Built-in 1-in. standoff design - keeps the post end elevated above the concrete surface to help prevent rot, and meets code requirements for structural posts installed in basements or exposed to weather or water splash.
• Increased uplift load capacity - engineered for earthquake and wind loading applications, giving builders confidence in high-demand structural connections.
• ZMAX galvanized coating - provides extra corrosion resistance beyond standard galvanization, making this post base a reliable choice for exterior environments and use with treated wood.
• Multiple fastening options - installs with 0.162 in. x 3-1/2 in. nails, Strong-Drive SD Connector screws, or 1/2 in. diameter machine bolts, offering flexibility to match jobsite fastening methods.
• Base gauge 12, strap gauge 10 steel construction - the heavier strap gauge delivers added strength where uplift forces are greatest, supporting maximum load performance in the connection.

Why This Product

• Adjustability built into the design - the slotted base hole means minor anchor bolt misalignment does not require costly corrections, making this standoff post base a practical choice for concrete-to-post connections in both new construction and retrofit projects.
• Rot protection and code compliance in one - the 1-in. standoff simultaneously shields post ends from moisture damage and satisfies code requirements for basement and weather-exposed structural posts, removing the need for additional protective measures.
• Engineered for high-stress load conditions - with increased uplift resistance for seismic and wind loading, this adjustable post base is suited to applications where a standard connector would fall short.
• ZMAX finish extends service life in harsh conditions - the extra layer of corrosion protection makes this post base well matched for treated lumber and outdoor use, where standard coatings may degrade prematurely.

Specifications

• MPN: ABU5-5Z
• Brand: Simpson Strong-Tie
• Member Size: 5-1/8 in. x 5-1/8 in.
• Steel Gauge: Base 12; Strap 10
• Width (W): 5-1/4 in.
• Length (L): 5 in.
• Height (H): 6-1/16 in.
• Standoff Height (HB): 1-3/4 in.
• Coating/Finish: ZMAX
• Install With: 0.162 in. x 3-1/2 in. nails or 1/2 in. diameter machine bolts
• Country of Origin: United States

Approved Applications

• Attaching wooden posts to existing concrete in high-capacity structural applications
• Structural posts installed in basements subject to code requirements for standoff height
• Exterior post installations exposed to weather or water splash
• Applications requiring increased uplift resistance for earthquake or wind loading
• Use with treated wood and engineered lumber in corrosive environments

Frequently Asked Questions

What post size is the ABU5-5Z designed to fit?

The ABU5-5Z is designed for use with 5-1/8 in. x 5-1/8 in. engineered lumber posts.

Why does the ABU5-5Z feature a 1-inch standoff?

The built-in 1-in. standoff helps prevent rot at the end of the post by keeping it elevated above the concrete surface. This design also meets code requirements for structural posts installed in basements or those exposed to weather or water splash.

What fasteners are used to install the ABU5-5Z?

This post base is installed with 0.162 in. x 3-1/2 in. nails or 1/2 in. diameter machine bolts. It can also be attached using Strong-Drive SD Connector screws.

Why is ZMAX galvanization important for this post base?

ZMAX galvanization provides extra corrosion resistance, making the ABU5-5Z well-suited for exterior applications and use with treated wood where standard galvanized finishes may not offer sufficient protection against the elements.

Note: Product dimensions may differ from picture. See item description for specifications.