The Simpson CBST66Z CBST ZMAX Standoff Column Base for 6x6 is a cast-in-place column base engineered by Simpson to deliver a secure, durable connection between 6x6 wood posts and concrete foundations in residential and light commercial construction. Built with a code-required 1 in. standoff design and a heavy-duty ZMAX galvanized finish, this post base is purpose-built for exterior environments and treated-wood applications where moisture exposure and corrosion are ongoing concerns.

Key Features

• Code-required 1 in. standoff design - elevates the wood post above the concrete surface, reducing direct moisture contact and protecting the post end against rot over the long term
• S-shaped bearing tabs - provide increased structural strength, allowing for higher download loads so the connection performs reliably under demanding conditions
• ZMAX galvanized coating - delivers extra corrosion resistance for exterior installations and applications involving treated wood, where standard coatings may fall short
• Dual-gauge steel construction (base 12, strap 10) - pairs a sturdy base with a heavier strap for a well-balanced, high-strength assembly that holds its form through installation and in service
• Designed for nominal 6x6 column size - ensures a precise, code-compliant fit with standard 6x6 wood posts used in decks, pergolas, carports, and light commercial structures

Why This Product

• Built-in rot protection from day one - the 1 in. standoff keeps the post end clear of the concrete slab, addressing one of the most common causes of premature wood post failure in outdoor post-to-foundation connections
• Corrosion resistance engineered for tough environments - ZMAX galvanization makes this column base a dependable choice for exposed exterior settings and treated-lumber applications where long-term durability matters
• Higher load capacity without upsizing - the S-shaped bearing tab design increases download strength within the same footprint, giving builders and contractors greater structural confidence for 6x6 post installations
• Trusted construction from a recognized structural connector brand - manufactured in the United States by Simpson, the CBST66Z reflects the same engineering standards relied on across residential and light commercial framing projects

Specifications

• Model Number: CBST66Z
• Member Size: 6x6
• Width 1: 5-1/2 in.
• Width 2: 5-1/2 in.
• Depth: 6-7/8 in.
• Height: 8-3/4 in.
• Gauge: Base 12; strap 10
• Coating: ZMAX
• Finish: ZMAX
• Install With: Install with (2) 5/8 in. diameter machine bolts (sold separately)
• Country of Origin: United States

Approved Applications

• Wood post-to-concrete foundation connections in residential construction
• Wood post-to-concrete foundation connections in light commercial construction
• Exterior applications requiring enhanced corrosion resistance
• Installations involving treated wood where ZMAX coating is recommended

Frequently Asked Questions

What is the purpose of the 1 in. standoff design on the CBST66Z?

The code-required 1 in. standoff elevates the wood post above the concrete surface, reducing direct contact with moisture and significantly lowering the risk of post-end rot over time.

What post size is the CBST66Z designed to fit?

The CBST66Z is designed for a nominal column size of 6x6, making it suitable for standard 6x6 wood posts used in residential and light commercial construction.

What fasteners are required to install the CBST66Z?

Installation requires (2) 5/8 in. diameter machine bolts, which secure the base to the concrete foundation.

Why is ZMAX galvanization important for this column base?

ZMAX galvanization provides extra corrosion resistance, making the CBST66Z well-suited for exterior environments and applications involving treated wood where standard coatings may be insufficient.

Note: Product dimensions and/or screw or bolt holes may differ from picture. Please see item description for specifications.