How to Install Deck Railing Posts - Both Wood and Metal

Whether you're completing a new deck build on your home or looking to renovate your outdoor space with a DIY deck railing makeover, learning how to install a deck post on your deck surface is an essential part of the process. You can install deck railing posts on any deck or patio surface including pressure-treated wood, composite deck boards, concrete, brick, and more easily as long as you're using the correct fastener.

Not sure where to begin with deck railings? Worried about staying in line with your building code? Not sure how to get started with installation? No worries!

Read on for a collection of all the best tips from our team of expert deck designers so that you can build a better deck, one post at a time. For more pro tips and deck project planning, give our team a call at 1-888-824-5316.

The Importance of Railing Posts for Deck Building

Posts are the basic support of your deck railing.

Your deck is essentially an elevated outdoor floor, supported by a frame and joists. The mounted railing is what makes it safe for people to be on your deck, especially children and pets, as it provides support and prevents falls. Railing is an essential piece of framing for any deck that's higher than 30 inches off the ground. Railing - most importantly, the posts that support your railing - must be installed properly to function as a successful safety feature.

Deck Railing should be able to:

  • Support someone leaning against it
  • Support someone pushing against it
  • Secure built-in seating or storage (if desired)
  • Hold up decorative accents like railing planters or decorative lights

While your plans for your deck may change over the years, your railing should be able to support all of them. And railing posts are the foundation of any strong deck railing.

Before You Begin

Before you begin installing your deck railing, especially the posts, it is essential to research your local building code. You should also look into the rules set by your homeowners’ association, if you have one.

Building codes vary widely depending on where you live, and each location has a different local building code. You can’t do any kind of construction unless you’re up to code, so take the time to dig into the details or hire an expert to help you.

If you have a homeowners’ association, take a look at their rules as well. Just because your building code allows something doesn’t mean your HOA does.

You should also ensure you have the right hardware required to install your chosen rail design. Some anchors need a bolt or two, some need nails. It depends on how the post is mounted to your deck surface. The easiest way to do this is to purchase a complete railing set with all the necessary hardware, usually in the form of a base kit.

Here’s a run-through on how to install deck railing posts made of either wood or metal:

How to Install a Wood Deck Post

The quickest and most secure way to mount a wooden 4x4 or 6x6 deck post to an existing deck surface is via a Titan Post Anchor. Titan Anchors provide a solid, powder-coated steel connection point for your wooden post to attach to the surface below. Be sure that you have at least 4 inches of blocking or substructure beneath your post location for a secure attachment.

Titan Post Connectors provide a sturdy, solid method of installing a deck railing post

Titan Post Anchor

To install a deck post with the Titan Post Anchor, first use a Hole Saw to create an opening in the bottom of your wooden deck post. Insert the top portion of the post anchor into the opening, and then drive the included fasteners through the pre-drilled openings. With your anchor attached, fasten the anchor to the deck surface with four structural screws or lag bolts.

  • When installing a deck post on a wood or composite decking surface, feel free to use any structural screws or lags that are at least 4 inches in length, such as the GRK RSS screws.
  • When mounting a deck post base kit on concrete or stone deck or patio surfaces, we recommend using specific concrete screws such as the Caliburn XL Screw from GRK.

How to Install a Metal Post

The AFCO Pro Post Kit arrives ready to install with included post cap and post skirt

Mounting a structural post or a metal deck railing post couldn't be any easier! These posts will all feature a pre-welded base plate at the bottom with pre-drilled screw openings in the corners. Simply place your post in position per your deck railing layout, ensuring that you have at least 4 inches of blocking underneath, shim and adjust until plumb, then drive your fasteners fully in place.

  • When installing a deck post on a wood or composite decking surface, feel free to use any structural screws or lags that are at least 4 inches in length, such as the GRK RSS screws.
  • When mounting a deck post base kit on concrete or stone deck or patio surfaces, we recommend using specific concrete screws such as the Caliburn XL Screw from GRK.

No matter your deck setup, DecksDirect has the largest selection of posts and mounting options that ship to you fast. To get your project moving, give our design team a call at 1-888-824-5316 to learn more or set up a project estimate.


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Learn more about the basics of deck framing and building in our Deck Framing Guide and learn deck parts and terminology in the DecksDirect Glossary of Deck Terms and Lingo.

Browse more deck design and railing style notes to upgrade your backyard space and deck in the DecksDirect Railing Style Guide: the quickest way to learn if your home is more suited for a classic aluminum deck railing or a strong, composite railing line.

The more you know, the better your deck and backyard projects will be! Whether you're looking at a brand new start or a fresh end-of-season deck renovation, give our deck designers a call at 1-888-824-5316 or send us an email at hello@decksdirect.com. Our deck experts will help you get the information, products, and tools you need for an awesome deck completely personalized to your needs!