The Simpson BC40R BC Galvanized Post Base for 4x Rough from Simpson is a light-duty post base designed to secure the bottom of a rough-cut 4x post or column to a wood deck or concrete surface. Built from 18-gauge steel with a G90 zinc galvanized finish, this post base delivers a strong, reliable mechanical connection for decks, patio covers, and similar top-supported applications where a positive post-to-surface anchor is essential.

Key Features

• Positive post-to-deck connection - creates a secure mechanical attachment between post and surface, giving your structure a solid, stable base rather than relying on friction or gravity alone
• Stronger than angled nailing or screw fastening - engineered to outperform improvised fastening methods, helping ensure the structural integrity of decks and patio covers over time
• Reduces the chance of the post splitting and eliminates nailing into end grain - protects the lumber at its most vulnerable point, extending the life of both the post and the connection
• Made from 18-gauge steel - provides a sturdy, rigid base that holds its form through installation and under load
• G90 zinc galvanized finish - adds a layer of corrosion resistance well suited for outdoor environments where moisture and weather exposure are ongoing concerns
• Sized for 4x rough lumber - fits nominal rough-cut 4x posts precisely, ensuring a proper fit without the gaps or play that can occur when using a base sized for surfaced dimensional lumber
• Not recommended for non top-supported installations such as fences or unbraced carports - knowing the right application upfront helps you select the correct base and avoid potential structural issues

Why This Product

• A mechanical connection built for rough-cut lumber - the BC40R is specifically sized for nominal 4x rough posts, making it the right fit for timber framing, deck construction, and patio cover projects that use rough-cut stock rather than surfaced dimensional lumber
• Greater strength where it matters - by providing a positive connection that is stronger than angled nailing or screw fastening alone, this post base adds meaningful structural reliability to light base applications on decks and patio covers
• Corrosion resistance for outdoor use - the G90 zinc galvanized coating is applied specifically to hold up in outdoor conditions, making this base a practical choice for deck framing and post connections exposed to the elements
• Protects the post and simplifies installation - eliminating end-grain nailing and reducing the risk of post splitting means less chance of damage during installation and a longer-lasting connection once the project is complete

Specifications

• Manufacturer Part Number (MPN): BC40R
• Brand: Simpson Strong-Tie
• Member Size: 4x rough
• Width 1: 4 in.
• Length 1: 4 in.
• Height 1: 3 in.
• Gauge: 18
• Coating/Finish: Zinc Galvanized, G90
• Install With: 16d common nails (sold separately)
• Fasteners Required: Post Flange - (6) 0.162 x 3-1/2" Nails; Base Bottom - (4) 0.162 x 3-1/2" Nails (sold separately)
• Country of Origin: United States

Approved Applications

• Decks and deck framing post connections
• Patio covers requiring post-to-surface base connections
• Light base applications attaching posts or columns to concrete or wood surfaces
• Top-supported post installations

Downloads and Resources

• View Spec Sheet

Frequently Asked Questions

What post size is the BC40R designed for?

The BC40R is designed for nominal 4x rough-cut lumber. It is not intended for standard dimensional (surfaced) 4x lumber.

What fasteners are required to install the BC40R?

Installation requires 16d common nails. Specifically, the post flange requires (6) 0.162 x 3-1/2" nails and the base bottom requires (4) 0.162 x 3-1/2" nails.

Is the BC40R suitable for outdoor use or exposure to moisture?

Yes. The BC40R features a G90 zinc galvanized finish, which provides extra corrosion resistance, making it well suited for outdoor applications such as decks and patio covers where exposure to moisture is a concern.

Can the BC40R be used for fences or unbraced carports?

No. The BC40R is not recommended for non top-supported installations, such as fences or unbraced carports. It is intended for light base applications where the post is top-supported.

Note: Product dimensions and/or nail or screw hole configurations may differ from the product image. Please refer to the item description for full specifications.