How to Prevent Sagging & Sinking Decks

Before you dig your frost footings, you will want to make sure the soil is properly compacted to support the deck load. Often when new houses are built, the process of digging the foundation disrupts the soil and leaves the yard unsettled. This means the entire yard will slowly drop in elevation relative to the house.
It is not uncommon for this to cause patios and driveways to crack. Likewise, if you anchor a deck to footings that are built on soil that is not properly compacted, your deck will probably sink. Needless to say, this is something you want to avoid. If you suspect your soil is unsettled, you will either have to wait for the yard to settle or dig the footings to a depth where the ground is compact. Certain kinds of soils are more problematic than others. Clay soils are particularly prone to shrinking and swelling. If you live in a new house, you may want to talk to your builder or local building inspections department to see if they have any information or suggestions. You can mark the level of the yard as it meets the house where you will be building your deck and observe it over a couple of months to see if you notice any change. If you have reason to believe settling may cause you problems, you may consider hiring a soil engineer to assess the situation, but this will result in an added cost to your project.
Cutting a Concrete Pad
Learn how to use a concrete saw to cut a hole in a patio slab to install a deck footing.
Soil Conditions
Learn how soil conditions can affect the size of your deck footings. Do you have gravel, sand or clay soil?
Protecting From Collapse
Learn how to use cardboard sonotubes and hole covers to protect your deck footing holes from caving in and flooding before pouring concrete.
How to Decorate Deck Support Columns
Browse some examples of decorative deck support posts for tall decks.
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.
Building a Balcony Deck
Learn information about balcony decks that use cantilevered joists that attach to house floor truss systems.
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Explore Articles by Topic

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Information related to installing frost footings for decks

Framing
Learn structural framing methods

Decking
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Railings
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Features
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Design
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Planning
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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
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.
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Find out what to do if your deck footing holes fill up with water.
Layout Deck Foundations
Learn how to lay out your deck footings accurately using triangulation with our step-by-step instructions.
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 Create Strong Post-to-Beam Connections
Learn how to create a positive structural connection for your post to beam connections. Use lag bolts, through bolts with washers, support cleats and hardware connectors.
Deck Floor Joists
Step-by-step instructions and tips on how to frame. Learn how to install treated wood joists and beams to build a strong deck.
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