Description

Key Features

Adjusts Around the Anchor

The slotted base hole gives you some movement around the anchor bolt, so setting a 4×6 post exactly where you need it is a lot easier. That matters when you’re lining up beams, rails, or existing framing.

Built-In 1 Inch Standoff

The raised base keeps the post off the concrete to help reduce moisture exposure at the end grain. It also meets code requirements for structural posts used in basements or areas exposed to weather or splash.

Heavy 12-Gauge Base

This Simpson Strong-Tie post base is made from 12-gauge steel with a ZMAX finish for exterior and treated-wood applications. You get a connector built for real deck and patio-cover loads, not just light-duty bracing.

Overview

The Simpson Strong-Tie ABU46Z Adjustable Post Base is a retrofit wood-to-concrete connector for attaching a nominal 4×6 wood post to existing concrete. This is a post base designed for deck, patio cover, and other top-supported structural post connections. Model Number: ABU46Z. If you are setting a post on an existing slab or footing and need high-capacity uplift performance with some room to fine-tune placement, this is the hardware built for that job.

What makes the ABU46Z worth using is the combination of adjustability and standoff protection. The base has a slotted anchor hole that gives you flexibility around the anchor bolt, which helps when the anchor is already set and your post location needs to land cleanly under a beam or header. Instead of fighting a fixed hole and hoping the layout works out, you get some practical adjustment during installation.

The built-in 1 inch standoff is not just a detail on paper. Keeping the post off the concrete helps reduce moisture sitting at the end of the post, which is one of the common failure points in exterior wood construction. Simpson Strong-Tie also notes that this standoff design meets code requirements for structural posts installed in basements or where weather and water splash are a concern. For decks and patio covers, that matters.

On the material side, the ABU46Z is made from 12-gauge steel with a ZMAX galvanized finish. That finish is intended for exterior and treated-wood applications where corrosion resistance is a real concern, not an afterthought. The connector is sized for a nominal 4×6 post and uses a 5/8 inch anchor along with either (12) 0.162 x 3-1/2 inch nails or two 1/2 inch bolts to secure the post, depending on the installation method you choose.

From a layout standpoint, the dimensions are compact enough to fit the post properly while still giving you the strength expected from the ABU series. For the ABU46Z, the listed dimensions are 3-9/16 inches wide, 5 inches long, and 7 inches high, with a 2-5/8 inch standoff dimension. The connector is sold individually, so it works well whether you are replacing a single damaged base or building out a full run of post supports.

This base is designed for existing concrete and high-capacity applications, not free-standing posts with no top support. Simpson specifically notes that post bases do not provide enough 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. Used where it is intended, under a properly braced structural assembly, the ABU46Z is a very solid solution.

The Simpson Strong-Tie ABU46Z Adjustable Post Base is a good fit for deck builders, framing contractors, remodelers, and serious DIY users working on structural exterior projects. If you need a 4×6 post base for retrofit concrete work and you want easier post alignment, code-friendly standoff spacing, and strong uplift performance, this is one of the smarter choices in the category.

Easier Layout on Existing Concrete

Retrofit work gets a lot easier when the connector gives you some room to work with. The ABU46Z is built for existing concrete, and the slotted base hole helps you dial in post position instead of rebuilding the anchor layout around a fixed point.

• Designed to attach a wood post to existing concrete in high-capacity applications
• Slotted anchor hole allows adjustability around the anchor bolt for more precise post placement

Key Specifications

Nominal Post Size	4 x 6
Material	Steel
Gauge	12 ga.
Finish	ZMAX galvanized
Width (in.)	3 9/16
Length (in.)	5
Height (in.)	7
Standoff / HB (in.)	2 5/8
Anchor Diameter (in.)	5/8
Post Fasteners	(12) 0.162 x 3-1/2 in. nails or (2) 1/2 in. bolts
Allowable Uplift	2,405 lb
Allowable Down Load	2,265 lb
Allowable Lateral / 100	12,520 lb
Weight (lbs)	3.66

Compatibility

Post Size

Fits nominal 4 x 6 wood posts.

Anchor Hardware

Uses a 5/8 inch anchor. Simpson lists retrofit anchor options such as Titen HD, Stainless-Steel Titen HD, or SET-3G adhesive anchors.

Post Fasteners

Installs to the post with 0.162 x 3-1/2 inch nails, Strong-Drive SD Connector screws, or 1/2 inch bolts.

Built For

Deck Building Patio Covers General Contracting Remodeling Exterior Structural Posts Wood to Concrete Connections Retrofit Installations DIY / Hobbyist

Pro Tip

Before tightening the anchor nut, set the post in the base and use the slot to fine-tune its final position under the beam or header. Also make sure the anchor does not extend more than 1 inch above the concrete, or it can interfere with the standoff area.

Warranty & Support

Warranty listed by Lowe’s: None.

Tool Nut’s Take

Tool Nut’s Take

Simpson Strong-Tie ABU46Z Adjustable Post Base for Clean Retrofit Work

If you’re setting a 4×6 post on existing concrete and want a connector that gives you adjustability without giving up strength, this is the one we would reach for.

• Who it’s for: Deck builders, remodelers, and serious DIY users installing top-supported 4×6 posts on cured concrete.
• Why it stands out: The slot around the anchor makes layout less frustrating, and the built-in standoff helps protect the post where moisture usually does the damage.
• Worth knowing: This is meant for top-supported structural posts. It is not the right choice for free-standing posts where rotation at the base is a concern.

Common Questions

• What size post does this base fit? The ABU46Z fits a nominal 4 x 6 wood post.
• Can it be used on existing concrete? Yes. The ABU series is designed to attach wood posts to existing concrete in retrofit applications.
• What fasteners does it use at the post? The listed post fasteners are (12) 0.162 x 3-1/2 inch nails or (2) 1/2 inch bolts. Simpson also states Strong-Drive SD Connector screws can be used.
• Does the base hold the post off the concrete? Yes. It has a built-in 1 inch standoff to help reduce moisture exposure at the post end.