The Simpson CB88RHDG Hot-Dip Galvanized Column Base is built to create a secure, code-compliant connection between 8x8 rough nominal posts and concrete foundations. Suitable for a wide range of lumber, glulam, and engineered wood product sizes, this heavy-duty base is cast-in-place or wet set into concrete so the bottom of the base plate sits flush with the concrete surface, delivering full post bearing and maximum load transfer. The CB series is the go-to solution for structural columns that require high structural values and rugged performance in demanding conditions - including exterior environments and applications involving treated wood.

Key Features

• Increased uplift resistance for wind or seismic loading - keeps posts anchored under the lateral and upward forces that challenge structural columns in high-wind or seismic zones, helping protect the integrity of the overall structure.
• Bolt hole locations meet code-required spacing for optimal capacity - eliminates guesswork during installation and ensures the connection performs at its rated structural values right out of the box.
• Strap 3 ga. / base 7 ga. steel construction - heavy-gauge steel at both the strap and base plate delivers the strength and rigidity needed for high-load column applications.
• Hot-dip galvanized finish - provides extra corrosion resistance specifically suited to exterior installations and connections involving pressure-treated lumber, extending the service life of the connector in harsh environments.
• Cast-in-place or wet-set installation - two compatible installation methods give contractors flexibility on the job site while keeping the base plate flush with the concrete surface for full post bearing.

Why This Product

• Purpose-built for high-load structural columns - the CB88RHDG is engineered specifically for columns that demand high structural values and rugged performance, making it a reliable choice where a standard post base is not enough.
• Hot-dip galvanization goes beyond standard coatings - the HDG finish is well-suited for exterior post bases and treated-wood column connections where long-term corrosion resistance is a critical requirement, not just a convenience.
• Designed for wind and seismic uplift conditions - the increased uplift resistance built into this column base makes it a practical fit for projects in regions where building codes call for enhanced resistance to wind or seismic forces.
• Versatile compatibility across wood product types - works with a wide range of lumber, glulam, and engineered wood products in the 8x8 rough nominal size, giving builders flexibility when selecting post materials for a project.

Specifications

• Manufacturer Part Number (MPN): CB88RHDG
• Nominal Column Size: 8x8 Rough
• Coating / Finish: Hot-Dip Galvanized (HDG)
• Steel Gauge - Strap: 3 ga.
• Steel Gauge - Base: 7 ga.
• Installation Hardware Required: (2) 3/4-in. diameter HDG machine bolts
• Country of Origin: United States

Approved Applications

• Connecting posts and columns to concrete foundations
• Compatible with a wide range of lumber, glulam, and engineered wood product sizes
• Cast-in-place or wet-set concrete installation
• Exterior applications and treated-wood environments requiring enhanced corrosion resistance
• Structural columns subject to wind or seismic uplift loading

What's Included

• 1x Simpson CB88RHDG Hot-Dip Galvanized Column Base for 8x8 Rough
• Note: Installation requires (2) 3/4-in. diameter HDG machine bolts (sold separately).

• Contact us for Configurable Options and Special orders

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

Frequently Asked Questions

What column size is the CB88RHDG designed for?

The CB88RHDG is designed for a nominal 8x8 rough column size. It is compatible with a wide range of lumber, glulam, and engineered wood product sizes in that nominal dimension.

How is the CB88RHDG installed into concrete?

The CB88RHDG is installed by either casting it in place or wet setting it into concrete. In both methods, the bottom of the base plate sits flush with the concrete surface to provide full post bearing. Installation requires two 3/4-in. diameter hot-dip galvanized machine bolts.

Why is the hot-dip galvanized finish important for this column base?

The hot-dip galvanized (HDG) coating provides extra corrosion resistance, making the CB88RHDG well suited for exterior applications and installations involving treated wood, where standard coatings may be insufficient to withstand the elements or the chemicals present in treated lumber.

Is the CB88RHDG suitable for use in high-wind or seismic zones?

Yes. The CB88RHDG features increased uplift resistance specifically for wind or seismic loading, and its bolt hole locations meet code-required spacing for optimal load capacity, making it appropriate for structural columns subject to these demanding conditions.