How to Splice a Deck Beam Over a Support Post
It is always best to use a continuous beam without seams for higher strength. Dimensional lumber is readily available in lengths up to 20’ which should accommodate a seamless beam for most applications. However, if your span is greater than 20’ (like the image below) you will likely need to splice some boards to form a beam. In order to do this you should overlap the individual parts of the beam so they are staggered if possible. It is best to have one continuous board over a post allowing one joint to fall on top of the post. Overlapping seams integrates strength and prevents fracturing along seams throughout the length of the beam. Always split a beam over a post.
Plan ahead and layout the beam on the ground over the footings before installation. For instance you could use 2-2x10x10’s and 2-2x10x20’s to form a 30’ beam with one seam set above two intermediate posts. You can also use hardware applications like strap ties or nailing plates to further secure the connection. Because these connectors are not particularly attractive you will probably want to conceal them behind fascia or on the interior side of the beam.
In this case we had to splice 2 sections of beam over a center post with a seam.
How to Decorate Deck Support Columns
Browse some examples of decorative deck support posts for tall decks.
How To Build an Octagon Deck
Learn how to build an octagon-shaped deck. Octagon decks can be used as the floor for a gazebo roof.
Framing a Deck Parallel to a House
Learn about an alternative framing method that allows you to install your decking perpendicular to the house and makes the deck free standing.
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.
How to Build a Floating Deck
A deck does not need to be attached to a house. Building a floating deck allows you the opportunity to create that perfect outdoor space anywhere on your property. Find out if a floating deck is the best option for your new outdoor oasis.
Tile decking
Installing tile over a standard deck frame in an exterior environment is a recipe for trouble.
More Helpful Resources
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 Blocking: Spacing, Methods, and How to Install Like a Pro
Learn the importance of deck blocking and how to install it when building your deck.
Building a Deck Around a Tree
Learn how to build a deck around a tree to allow the tree to grow and not damage its root system while digging footings.
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.
Picture Frame Decking
Install a picture frame or perimeter board to finish the edge of your deck with style.
Introduction to Decking
Spacing between deck boards provides several critical functions, such as drainage & drying. Learn how to space and stagger deck boards at Decks.com.
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