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Build your project on strength and style with the Avant Post Base by Simpson Strong-Tie. Simpson post bases are the ideal foundation choice for outdoor projects like pergolas, pavilions, patio covers and more to keep your column bases and wood posts secure and strong.

Crafted from ZMAX® galvanized steel, the Avant adjustable post base is corrosion-resistant and features a rich, black powder-coated finish. With a one-inch rise from the ground surface, this Simpson Strong-Tie base will protect your wood post bases and column ends from rotting by preventing contact with groundwater and moisture.

Simpson post and column bases are perfect for wood to concrete connections, among others. The Avant base anchors a wood post or support column to a concrete, brick or wood surface with reliable strength.

To complete installation of the Avant Side Plates to the Simpson Strong-Tie Base you'll need additional hardware. The Structural Wood Screws and Hex Head Washers will secure the plates and give the finished look of fortified pergola.

Simpson Post Bases - Sizes

Avant Post Bases are sold individually and are offered to fit both nominal and rough-cut 4 in x 4 in, 6 in x 6 in, 8 in x 8 in, or 10 in x 10 in post lumber sizes.


DecksDirect # 45875
simpson strong tie

Technical and Installation Notes

Pack SizeEach
MaterialZMAX® galvanized 12 gauge steel with black powder-coat
Lumber Sizes4 in x 4 in, 6 in x 6 in, 8 in x 8 in, and 10 in x 10 in
Lumber TypeNominal or Rough Cut

(length x width x height)

4 in x 4 in, Nominal: 3 in x 3-9/16 in x 6-3/4 in
4 in x 4 in, Rough Cut: 3 in x 4-1/16 in x 6-1/2 in

6 in x 6 in, Nominal: 5 in x 5-1/2 in x 6-13/16 in
6 in x 6 in, Rough Cut: 5 in x 6 in x 6-9/16 in

8 in x 8 in, Nominal: 7 in x 7-1/2 in x 9-3/8 in
8 in x 8 in, Rough Cut: 7 in x 8 in x 9-1/8 in

10 in x 10 in, Nominal: 9 in x 10 in x 9-1/2 in
10 in x 10 in, Rough Cut: 9 in x 9-1/2 in x 9-3/4 in

Hardware Needed Structural Wood Screws and Hex Head Washers sold separately
Warranty View Simpson Warranty Information
Outdoor Accents Hex Head Washer by Simpson Strong-Tie
Starting at: $19.99
Outdoor Accents Structural Wood Screw by Simpson Strong-Tie (3-1/2 in)
Starting at: $15.99
Strongly anchor pergola, arbor, and pavilion posts to wooden beams with the Simpson Strong-Tie Avant Joist Tie.
Starting at: $10.99
Once installed, the Avant Side Plates from Simpson Strong-Tie create a beautiful and strong-looking post base.
Starting at: $25.99
FortressAccents™ Vertical LED Post Light - Gloss Black
Starting at: $52.99
Outdoor Accents Mission Collection Adjustable Post Base by Simpson Strong-Tie - 6 in x 6 in - installed
Starting at: $36.99
Post Anchor by Titan - 6x6 - with Hardware - Package Contents
Starting at: $22.99
Find your favorite afternoon nap spot with the LINX Hammock Kit by Wild Hog Railing installed in the LINX Pergola system.
Starting at: $285.99
The LINX TRIFIT post to beam connector is crafted from high-grade steel and features a beautiful black powder-coat finish.
Starting at: $89.99
The LINX UNIFIT pergola post base kit features a pre-welded base plate with screw openings for a quick, secure post attachment.
Starting at: $62.99

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