The Simpson 5 x 5 Black Composite-Plastic Standoff Post Base is an engineered composite-plastic standoff base from Simpson, built for securing solid wood columns and structural posts to concrete surfaces in both interior and exterior applications. The base attaches to the bottom of the column and to concrete using threaded rod and epoxy, delivering a code-required 1-inch standoff that keeps wood elevated above the concrete surface. Load rated and available in shapes to match a variety of column sizes, this standoff base pairs structural confidence with a clean black finish suited to decorative and functional installations alike.

Key Features

• Sized for nominal 5x5 posts or columns - fits the exact member size your project requires without modification or guesswork.
• Provides the code-required 1-inch standoff - keeps the base of the wood column elevated above the concrete surface, helping protect structural and decorative posts from prolonged moisture contact.
• Engineered composite plastic construction - will not rust or corrode, making it a dependable choice for exposed outdoor environments as well as covered indoor installations.
• Black finish - delivers a clean, custom appearance that suits both structural and decorative column applications without additional finishing work.
• Load rated for structural use - provides the engineering documentation and performance assurance needed for code-compliant installations.

Why This Product

• Built for real outdoor exposure - the composite plastic material resists rust and corrosion, so this post base holds up in the wet, variable conditions that would compromise a standard metal base over time.
• Satisfies code requirements out of the box - the built-in 1-inch standoff meets code-required clearance between the wood column and the concrete surface, reducing the need for field improvisation on inspected projects.
• Versatile attachment method - the base connects to concrete via threaded rod and epoxy, giving installers a secure, low-profile anchor point suited to both new construction and retrofit applications on concrete slabs, piers, or footings.
• Made in the United States by Simpson - comes from a manufacturer with an established reputation in structural connectors and post bases, giving contractors and homeowners a load-rated, documented solution they can specify with confidence.

Specifications

• Manufacturer: Simpson Strong-Tie
• MPN: CPS5
• Nominal Post Size: 5x5
• Material: Composite Plastic
• Finish: Black Composite Plastic
• Width: 4-1/8 in.
• Length: 4-1/8 in.
• Standoff Height: 1 in.
• Installation Fasteners: Install with (4) 0.148-in. x 3-in. nails and (1) 5/8-in. diameter anchor bolt (sold separately)
• Country of Origin: United States

Approved Applications

• Attaching solid wood columns to concrete surfaces indoors and outdoors
• Providing a code-required 1-inch standoff between post base and concrete
• Use with nominal 5x5 structural posts or decorative columns
• Concrete attachment using threaded rod and epoxy

Frequently Asked Questions

What size post or column is the CPS5 designed for?

The CPS5 is designed for use with a nominal 5x5 post or column.

What fasteners are required to install the CPS5?

Installation requires (4) 0.148-in. x 3-in. nails and (1) 5/8-in. diameter anchor bolt. The base attaches to concrete using threaded rod and epoxy.

Can the CPS5 be used outdoors?

Yes. The CPS5 is designed for use both indoors and outdoors. The engineered composite plastic construction will not rust, making it well suited for exposed exterior environments.

Why is a standoff post base important?

The CPS5 provides a code-required 1-inch standoff between the base of the wood column and the concrete surface. This gap helps protect the structural post from prolonged contact with moisture, contributing to the long-term integrity of the installation.

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