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.
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Avoid problems related to digging deck footings near retaining walls. Learn some tips from the pros for how to handle these difficult situations.
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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.
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Browse some examples of decorative deck support posts for tall decks.
How to Install Wood Deck Support Posts
Installing wood deck posts on top of concrete footings will provide additional support for your deck. We recommend using 6x6 posts due to their strength. Learn how install them at Decks.com.
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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