Soil Conditions For Deck Footings
Before you can calculate the size of your footings, you will need to know what kind of soil is present in your yard. Most soils can be classified into three categories: gravel, sand and clay.
Gravel: This type is primarily composed of small stone pebbles that you can see easily with the naked eye. Gravel feels rocky. You cannot roll this soil into a ball. Gravel will drain water very easily and can support the greatest amount of load (3000 lbs/sq ft).
Sand: Sand is composed of tiny particles that are difficult to see with the naked eye. Most sand is tan or white in color. Sand has a rough gritty texture. If you try to roll sand into a ball, it will not hold its shape. If you add water to sand, it will run through very quickly. Sand can support a load of 2000 lbs/sq ft.
Clay: You cannot see clay particles without a strong magnification. Clay feels sticky and can easily be rolled into a ball. It doesn’t drain water very easily. Clay can be many different colors depending on what other minerals it is mixed with. It is the weakest common soil type supporting a load of 1500 lbs/sq ft.
If you are unsure what soil type you will be working with, always use the worst case scenario, which is clay, to make your calculations.
Cutting a Concrete Pad
Learn how to use a concrete saw to cut a hole in a patio slab to install a deck footing.
Footing Size
Learn how large to make your deck footings. Use our table for maximum allowable loads to determine the proper size for your soil type.
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.
How To Build a Hexagon Deck
Learn some tips on how to build a six-sided hexagon-shaped deck.
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.
More Helpful Resources
Explore Articles by Topic
![Footings](/media/3vsas025/all-articles_footings-2x.png?format=webpg&quality=80)
Footings
Information related to installing frost footings for decks
![Framing](/media/5wrarsgy/all-articles_framing-2x.png?format=webpg&quality=80)
Framing
Learn structural framing methods
![Decking](/media/meljt4np/all-articles_decking-2x.png?format=webpg&quality=80)
Decking
Learn about wood and composite decking materials
![Stairs](/media/2sopl0br/all-articles_stairs-2x.png?format=webpg&quality=80)
Stairs
An in-depth look at the complex issue of how to build stairs
![Railings](/media/hpwbuyzr/all-articles_railings-2x.png?format=webpg&quality=80)
Railings
How to install guardrails and handrails to meet IRC code
![Features](/media/tvcahlmk/all-articles_features-2x.png?format=webpg&quality=80)
Features
An overview on water drainage, benches, planters and lights
![Design](/media/3bvpzvtz/all-articles_design-2x.png?format=webpg&quality=80)
Design
The basics of deck design
![Planning](/media/qdenqrqv/all-articles_planning-2x.png?format=webpg&quality=80)
Planning
Learn about permits and working with contractors
![Porches and Patios](/media/sg5bst1z/all-articles_porches-and-patios-2x.png?format=webpg&quality=80)
Porches & Patios
Build a covered deck to enjoy all seasons
![Ledger](/media/0htjl4uu/all-articles_ledger-2x.png?format=webpg&quality=80)
Ledger
Proper attachment techniques
![Care](/media/qdpnwkry/all-articles_care-2x.png?format=webpg&quality=80)
Care
Maintain your deck to maintain your investment
![Materials](/media/zqfflkeo/all-articles_materials-2x.png?format=webpg&quality=80)
Materials
An overview on water drainage, benches, planters and lights
How many footings do I need?
Learn how to determine the number of footings and support posts you need for your deck when designing your deck frame.
How to Buy Concrete: Hiring a Ready-Mix Truck
Hiring a truck to deliver ready-mixed concrete for your project may make better sense than mixing it yourself. Learn how to order concrete for your deck at Decks.com.
Digging Foundations
Learn how to hand dig or mechanically dig your deck footings with step-by-step instructions. Learn what to do if you hit a rock.
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.
Joist Tape: What Is It and Do I Need It?
Dive into the benefits of joist tape and why you need it for your deck build.
How to Install Deck Girder, Cantilever or Drop Beams
Learn about the pros and cons of installing a cantilever, girder or drop beam to support your deck joists. This method allows for a notched post-to-beam connection.
Explore Articles by Topic
![Footings](/media/3vsas025/all-articles_footings-2x.png?format=webpg&quality=80)
Footings
Information related to installing frost footings for decks
![Framing](/media/5wrarsgy/all-articles_framing-2x.png?format=webpg&quality=80)
Framing
Learn structural framing methods
![Decking](/media/meljt4np/all-articles_decking-2x.png?format=webpg&quality=80)
Decking
Learn about wood and composite decking materials
![Stairs](/media/2sopl0br/all-articles_stairs-2x.png?format=webpg&quality=80)
Stairs
An in-depth look at the complex issue of how to build stairs
![Railings](/media/hpwbuyzr/all-articles_railings-2x.png?format=webpg&quality=80)
Railings
How to install guardrails and handrails to meet IRC code
![Features](/media/tvcahlmk/all-articles_features-2x.png?format=webpg&quality=80)
Features
An overview on water drainage, benches, planters and lights
![Design](/media/3bvpzvtz/all-articles_design-2x.png?format=webpg&quality=80)
Design
The basics of deck design
![Planning](/media/qdenqrqv/all-articles_planning-2x.png?format=webpg&quality=80)
Planning
Learn about permits and working with contractors
![Porches and Patios](/media/sg5bst1z/all-articles_porches-and-patios-2x.png?format=webpg&quality=80)
Porches & Patios
Build a covered deck to enjoy all seasons
![Ledger](/media/0htjl4uu/all-articles_ledger-2x.png?format=webpg&quality=80)
Ledger
Proper attachment techniques
![Care](/media/qdpnwkry/all-articles_care-2x.png?format=webpg&quality=80)
Care
Maintain your deck to maintain your investment
![Materials](/media/zqfflkeo/all-articles_materials-2x.png?format=webpg&quality=80)
Materials
An overview on water drainage, benches, planters and lights