Simpson Strong-Tie CB Column Base for 8x8 (CB88)
Simpson Strong-Tie CB Column Base for 8x8 (CB88)
Key Features
Overview
The Simpson Strong-Tie CB88 CB Column Base for 8x8 is a cast-in-place column base designed to connect an 8x8 post to a concrete footing or foundation. This is a column base designed for post-to-concrete structural anchoring. Model Number: CB88. If you are building decks, porch roofs, or other top-supported structures where the post connection needs real load capacity, this connector is made for that job.
What sets the CB series apart is that it is meant for columns requiring high structural values and rugged performance. Simpson Strong-Tie calls out increased uplift resistance for wind or seismic loading, and that matters in the real world because the post base is not just supporting weight straight down. It also has to resist pull-up forces and keep the connection working when the structure sees lateral movement or weather-driven loads.
For the CB88 specifically, the nominal column size is 8x8, and the steel build is substantial: a 3-gauge strap paired with a 7-gauge base. In practical terms, that means this is not a light-duty decorative bracket. It is a structural connector intended for serious post support where bearing, bolt spacing, and embedment all affect the finished assembly.
The CB88 is installed cast-in-place or wet set into concrete with the bottom of the base plate flush with the concrete for full post bearing. That flush-bearing design is important because it allows the post load to transfer properly into the base and footing. According to Simpson Strong-Tie installation guidance, for full loads the minimum side cover required is 3 inches for CB models, and the connector should be installed with the bottom of the base plate flush with the concrete.
Bolt hole locations are laid out to meet code-required spacing for optimal capacity. Lowe's lists installation with (2) 3/4-inch diameter machine bolts. That gives you a clear starting point when planning the post connection, and it helps keep the field install aligned with how this base is intended to perform. As with any structural connector, using the specified fasteners is part of getting the published performance from the hardware.
From a material and finish standpoint, the CB88 is steel with a Simpson Strong-Tie gray paint finish in the standard version shown here. That painted finish is common for general use, and Simpson also notes that some CB products may be available with additional corrosion protection options depending on project requirements. If the base is going into an environment with higher corrosion exposure, that is worth checking before you order.
One thing worth being direct about: Simpson Strong-Tie states that post bases do not provide adequate resistance to prevent members from rotating about the base, so they are not recommended for non-top-supported installations such as fences or unbraced carports. That is not a flaw in the product. It is just the right-use-case line. The CB88 is for properly supported structural posts, not free-standing assemblies that rely on the base alone to stop rotation.
The best buyer for this connector is a deck builder, framing contractor, remodeler, or serious DIYer working on post-to-footing structural connections. If you need a cast-in-place 8x8 post base with real capacity, proper bolt spacing, and a known installation path from a major structural hardware brand, the CB88 checks the right boxes.
Heavy-Duty Post Support You Can Build Around
This is the kind of connector you use when the post base is part of the structural conversation, not an afterthought. The CB88 is sized for 8x8 posts and built to transfer load into concrete with full post bearing.
- Designed for wood-to-concrete cast-in-place applications
- Nominal 8x8 column size
- Gray painted steel construction
Hole Layout That Matches the Intended Load Path
The dimensions and bolt spacing are not random. They are laid out so the connector can be installed with the correct machine bolts and meet code-required spacing that supports the published capacity of the base.
- Bolt hole locations meet code-required spacing for optimal capacity
- Install with (2) 3/4-inch diameter machine bolts
- Built for columns that need high structural values and rugged performance
Key Specifications
|
Material |
Steel |
|---|---|
 Nominal Column Size |
8 x 8 |
 Depth |
7.5 in |
|
Width |
8.563 in |
 Weight |
11.4 lbs |
|
Strap Gauge |
3 gauge |
|
Base Gauge |
7 gauge |
 Finish |
Simpson Strong-Tie gray paint |
Built For
Pro Tip
When you set a CB88 in concrete, keep the bottom of the base plate flush with the concrete and maintain the required side cover. Simpson specifies 3 inches minimum side cover for full loads, so plan that footing size before the pour, not after.
Warranty & Support
Tool Nut's Take
Simpson Strong-Tie CB88 CB Column Base for 8x8 Is the Right Kind of Overbuilt
If you are setting an 8x8 post into a concrete-supported structural system, this is the kind of base you buy when you want the connection to be taken seriously.
- Who it's for: Deck builders, framers, remodelers, and serious DIY users handling structural post-to-concrete work.
- Why it stands out: Heavy steel, code-spaced bolt holes, and a design intended for high structural values instead of light-duty trim work.
- Worth knowing: This is for top-supported structures. Like other post bases, it is not meant to stop a free-standing post from rotating on its own.
Common Questions
- What size post does this base fit? It is designed for a nominal 8 x 8 column.
- How is the CB88 installed? It is installed cast-in-place or wet set into concrete, with the bottom of the base plate flush with the concrete.
- What bolts does it use? Lowe's lists installation with two 3/4-inch diameter machine bolts.
- Is this a good choice for a fence or other free-standing post? No. Simpson Strong-Tie states that post bases do not provide adequate resistance to prevent rotation in non-top-supported installations.