Building a Deck Near a Retaining Wall
If your footing locations will require you to dig next to a retaining wall, you will have to be very careful not to damage the wall. Disrupting the soil can cause a wall to cave in. This situation will usually require you to hand dig the footing. If you are digging above a retaining wall, you will have to dig deep enough to maintain the minimum frost depth away from the surface of the wall. This may result in digging some very deep footings.
All retaining walls have a system built into the wall construction that hides behind the wall. In a wood or timber retaining wall, you will see what is called a "deadman frame". These are members usually consisting of the same timber size that make up a skeletal frame backfill over the solid to keep the wall from bulging out or falling over. An interlocking concrete block wall will have a "geogrid" pinned into the wall over other course. These systems usually travel as far back as the wall is high, so if you plan to dig in these areas you will have problems.
Building a deck around a series of retaining walls can definitely present some problems. Under no circumstances should you ever consider setting a post on top of a retaining wall. The walls are not designed to resist this additional loading and could result in a catastrophic failure. Many of these problems should have been addressed during the design phase. Always use an extra degree of caution when working beside a retaining wall.
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.
Layout Deck Foundations
Learn how to lay out your deck footings accurately using triangulation with our step-by-step instructions.
How to Decorate Deck Support Columns
Browse some examples of decorative deck support posts for tall decks.
How to Splice a Deck Beam Over a Support Post
Follow our step by step tutorial for splicing a deck beam over a support post. Never split a beam in the center of a span.
How to Use a Triple Deck Beam to 6x6 Post Connection
Learn how to use a post beam connector to attach a 3-2x10 beam to a support post for a deck when there isn't enough material on the post to create a notched connection.
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Footings
Information related to installing frost footings for decks

Framing
Learn structural framing methods

Decking
Learn about wood and composite decking materials

Stairs
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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

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Build a covered deck to enjoy all seasons

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Proper attachment techniques

Care
Maintain your deck to maintain your investment

Materials
An overview on water drainage, benches, planters and lights
Building a Deck Near a Retaining Wall
If your footing locations will require you to dig next to a retaining wall, you will have to be very careful not to damage the wall. Disrupting the soil can cause a wall to cave in. This situation will usually require you to hand dig the footing. If you are digging above a retaining wall, you will have to dig deep enough to maintain the minimum frost depth away from the surface of the wall. This may result in digging some very deep footings.
All retaining walls have a system built into the wall construction that hides behind the wall. In a wood or timber retaining wall, you will see what is called a "deadman frame". These are members usually consisting of the same timber size that make up a skeletal frame backfill over the solid to keep the wall from bulging out or falling over. An interlocking concrete block wall will have a "geogrid" pinned into the wall over other course. These systems usually travel as far back as the wall is high, so if you plan to dig in these areas you will have problems.
Building a deck around a series of retaining walls can definitely present some problems. Under no circumstances should you ever consider setting a post on top of a retaining wall. The walls are not designed to resist this additional loading and could result in a catastrophic failure. Many of these problems should have been addressed during the design phase. Always use an extra degree of caution when working beside a retaining wall.
Cutting a Concrete Pad
Learn how to use a concrete saw to cut a hole in a patio slab to install a deck footing.
Can I use pier blocks?
Our inspector explains the pros and cons of using pier blocks for deck foundations.
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.
How to Decorate Deck Support Columns
Browse some examples of decorative deck support posts for tall decks.
How to Size a Deck Beam
Learn about how to choose the correct size beam for your deck. We discuss engineered beams and "sandwiched" style beams.
Determining Deck Beam Height
Learn how to measure in order to set your posts to properly position your deck beam to the correct height. We recommend sloping your deck to shed water away from the house.
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