How to Use Concrete Footings for Deck Posts
Concrete is, in fact, the most used material for construction in the world and has been in use since the age of the Roman Empire. Concrete is a mixture of aggregate (sand and gravel) combined with water and cement. Depending on the ratio of these parts, the concrete can be stronger or weaker. Concrete hardens in a process known as hydration, which is caused by the reaction between water and cement. Adding too much water can weaken the concrete.
For most deck projects, it is practical to buy bags of premixed concrete that are prepared by adding water and mixing. You can use a wheelbarrow and mix with a hoe to a consistency that is able to move and fill voids, but is not too wet and soupy. Hoes work better for mixing concrete than shovels. Renting a mixer can reduce your labor time by half. Be sure to follow the instructions listed on the packaging. It is possible to make your own concrete mix by combining 3 parts gravel, 2 parts sand and 1 part cement, but this requires more knowledge and skill than using premixed bags. Your footing should be at least as thick as it is wide at its base. The ideal temperature for pouring concrete is between 50-90 degrees F.
Make sure you use 5,000 psi concrete mix. Once you have poured half of the concrete into the tube, you should consolidate it with a shovel or a piece of rebar to eliminate air pocket voids. Pour concrete until it is overflowing the form tube and level off the top with a shovel.
Cutting a Concrete Pad
Learn how to use a concrete saw to cut a hole in a patio slab to install a deck footing.
Prevent Deck Sinking
Sinking deck footings can lead to serious problems. Learn what can cause concrete footings to sink. Properly installed footings will resist sinking.
Do I need to use rebar?
Our inspector discusses using steel rebar for deck footings.
How to Decorate Deck Support Columns
Browse some examples of decorative deck support posts for tall decks.
Using Shims to Level the Deck Surface
Install shims or notch joist bottom across uneven joists to level your deck surface.
Engineered Deck Beam
Use treated engineered deck beams for long spans with fewer posts and footings. Engineered beams can be designed and specially ordered from your lumberyard.
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Learn how to determine the number of footings and support posts you need for your deck when designing your deck frame.
Buried Post
Learn how to install a concrete deck footing with a buried treated support post as an alternative to a solid pier foundation.
Do I need to use rebar?
Our inspector discusses using steel rebar for deck footings.
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.
How To Build a Hexagon Deck
Learn some tips on how to build a six-sided hexagon-shaped deck.
Beam Span Chart
Learn how to size your deck beam using this easy-to-use span table. Just cross-reference the post spacing and joist length to determine the beam size.
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