How To
Framing
How to Install Wood Deck Support Posts

How To
Framing
How to Install Wood Deck Support Posts

Ready to Start Your Project?

Find Your Perfect Color

EXPLORE THE COLOR SELECTOR

Estimate Deck Costs

TRY THE COST CALCULATOR

Get Inspired

BROWSE PHOTOS, TIPS, AND IDEAS

You'll be redirected to Trex.com, our composite decking website.

Deck Support Columns

How to Install Wood Deck Support Posts

Written By: Decks Team

Published on August 04, 2004

In the past, many decks were built with 4x4 support posts (also called structural posts). But these can bow seriously, even if a deck is only 3 feet off the ground. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them. And if a deck is over 10 feet tall, you should install bracing.

This article shows installing non-notched posts on top of concrete footings that rise above the ground, to support framing that has already been built on temporary supports.

[tip] Wait for the Concrete to Cure

Allow at least two days for the concrete to cure before drilling holes and installing a post. If you install the post the same day as you poured the concrete, the footing could crack.

Mark the post’s corner on the footing.

1. The support post’s side should be flush with the outside of the beam or doubled header.

Draw the outline.

Use a level to mark the post’s corners, then use a square or straightedge to mark its outline.

Heavy-duty hammer drill.

You can try to drill holes in concrete with a standard 3/8-inch drill, but it will be very slow going. Save yourself time and energy by using a standard-voltage heavy-duty hammer drill like this one, which will bore down with ease.

Sleeve anchors.

Use sleeve anchors of a size recommended for your post base. The packaging will tell you the size of the drill bit to use, as well as how deep to drill the holes.

Mark for the hole.

2. Position the post base as shown with its inside area aligned with the pencil lines. Scribe a circle where the base’s lag screw will go.

Drill the Hole.

Drill a hole of the recommended size, a half inch or so deeper than the sleeve anchor. Pull out most of the dust by lifting the drill bit quickly as you drill, two or more times.

Tap the anchor in.

3. Reposition the post base, aligned with the layout lines, and tap a sleeve anchor down into the hole.

Tighten the bolt.

Use a crescent wrench or a socket wrench to tighten the nut, which will cause the anchor’s sleeve to expand so that it grips the concrete firmly.

Measure for post

4. Install a post cap, also called a post-to-beam connector, onto the beam or doubled joist above; use a level to be sure it is plumb with the post base.

Tap in the post.

Measure the distance between the two hardware pieces, then subtract 1/16 inch or so to account for imperfect cuts.

Use a hand sledge to tap the 6x6 into place, check for plumb, and drive nails into all the hardware holes to secure the post.

Finish with nails.

Use a hand sledge to tap the 6x6 into place, check for plumb, and drive nails into all the hardware holes to secure the post. With the posts in place, you can remove the temporary supports.

How to Decorate Deck Support Columns

Browse some examples of decorative deck support posts for tall decks.

Save

Deck Framing

Deck Joist Water Protection

Learn about a technique used by many pro builders for wrapping deck framing lumber with a waterproof barrier to prevent corrosion and rot.

Save

Deck Support Columns

How to Connect a Notched Wood Post to a Beam

Learn how to install a notched wood support post to cantilevered beam connection using lag bolts, through bolts with washers or structural screws.

VIEW MORE Framing ARTICLES

Next Step: Decking Articles

VIEW MORE Decking ARTICLES

Installing Composite Decking Over Concrete

Save

Decking Installation

How to Install Decking Over Existing Concrete Slab, Patio, or Porch

Discover the best techniques to build a deck over concrete, ensuring proper drainage and stability, while creating a beautiful outdoor space.

Save

Decking Installation

Decking over decking

No; this is not a recommended practice.

Save

Decking Installation

How to Install Composite Decking

Learn about how to install composite decking. Topics include expansion and contraction issues and hidden fastener systems.

VIEW MORE Decking ARTICLES

Get more helpful resources delivered right to your inbox

More Helpful Resources

EXPLORE THE DECK PLAN LIBRARY >

CALCULATE JOIST SPAN >

LEARN HOW TO BUILD A DECK >

Explore Articles by Topic

Footings

Information related to installing frost footings for decks

Framing

Learn structural framing methods

Decking

Learn about wood and composite decking materials

Stairs

An in-depth look at the complex issue of how to build stairs

Railings

How to install guardrails and handrails to meet IRC code

Features

An overview on water drainage, benches, planters and lights

Design

The basics of deck design

Planning

Learn about permits and working with contractors

Porches & Patios

Build a covered deck to enjoy all seasons

Ledger

Proper attachment techniques

Care

Maintain your deck to maintain your investment

Materials

An overview on water drainage, benches, planters and lights

Why is Joist Protection so Important for Your Deck?

If you’ve ever seen a piece of wood left out in the weather for any period of time, you know what happens: decay. Whether through wet rot, insect damage, or mildew, the fibers begin to break down.

Deck Frame Squaring With Carpenters Tools

Save

Deck Framing

4 Tried and True Methods on How to Square a Deck Frame

Discover the secrets to perfectly squaring your deck frame. Our guide simplifies the process, ensuring your deck is flawlessly shaped and structurally sound.

Save

Deck Support Columns

How to Install Deck Post Wraps and Sleeves

Learn how to install trim or post sleeves over your pressure-treated support posts for a cleaner finish and to protect the material from checking.

VIEW MORE Framing ARTICLES

Next Step: Decking Articles

VIEW MORE Decking ARTICLES

Save

Decking Installation

What to Consider When Building A Wrap-Around Deck

Looking to add a wrap-around deck to your home but unsure of what the process involves? Check out this guide to learn more about top considerations when building a wrap-around deck.

Save

Decking Installation

Best Hidden Deck Fasteners

Hidden fasteners create a clean deck surface and can be used with composite, wood and other materials. Learn about hidden deck fasteners at Decks.com.

Save

Decking Removal

How to Demolish & Remove a Deck

At some point, it might become necessary to remove an old deck, due to age or condition. Learn more about what's involved in a deck demolition and removal project.

VIEW MORE Decking ARTICLES

Get more helpful resources delivered right to your inbox

Explore Articles by Topic

More Helpful Resources

EXPLORE THE DECK PLAN LIBRARY >

CALCULATE JOIST SPAN >

LEARN HOW TO BUILD A DECK >