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Retaining Wall

I hope to build a retaining wall 5' and 6' tall by 44' long.

I had hoped to build it with a concrete footer, "cinder" blocks (filled with concrete) and slate veneer - but I am wondering how big & deep the footer should be to avoid future problems. We live in Atlanta so the frost depth is about an inch.

An alternative is to use concrete blocks from a home improvement store - but I don't really like the look, and they are only intended for walls up to 3'.

There is an existing retaining wall, actually part of the foundation which extends out about 6'. I would like to "extend" this wall with a 90 degree out-side turn, then 22' of 5' tall wall, then a 90 degree in-side turn, 5' of 6' tall wall, and finally a 90 degree out-sidet turn, and 17' of 6' tall wall.

Will footers 16" wide, 8" deep be sufficient?

Thank you

Re: Retaining Wall

I'm not familiar with the building code in Atlanta, but 8" is probably not deep enough for a retaining wall.
Check with your local building dept.

A. Spruce
Re: Retaining Wall

I would consult with the building department or a few local contractors. You're going to need a substantial footing to support the weight of that wall AND resist rotation from the hydraulic forces of the earth behind the wall. You'll likely have to have "tie-backs" as well, which are a part of the wall, but will go perpendicular to it back into the earth behind the wall.

Re: Retaining Wall


As someone who has built 200' of natural stone retaining walls over the years, I can advise that you have a LOT of work on your plate if you decide to take on building the wall you describe in your post.

This is considered very heavy work by most who are are involved in this type of activity; first of all, a wall 6' in height is too high to be attempted by anyone except a pro, or someone with lots of experience---there's usually no need for such a height, regardless of the slope of the hill, a procedure known as terracing is almost always used where two 3' walls are built, and the hill is cut back as needed to accomodate this tactic.

Second, there is usually no need to get into the pouring of costly & time-consuming footings or perpendicular tie backs----mortarless natural stone can be used to build a retaining wall without these elements, and the wall is "battered" or slanted into the hill slightly as each course of stone is laid up as the wall is built---the stones, usually between 12" to 18" long, 12" wide, and 4 to 6" thick are laid in overlapping course rows so that each stone of the 2nd & subsequent courses are laid over the seams of the previous row, as one would use in laying bricks, but without using any mortar.

You would have to consult with your town hall building dept. to see if a building permit is required for such work in your locality---stone is heavy & it's easy to hurt yourself; roll heavy stones along the ground rather than lifting & get help with the big ones.

A line of 4" plastic perforated pipe with an exit drain is installed surrounded by crushed stone in back & along the first course of stone, wrapped in landscape fabric, or a fabric "sleeve" to prevent clogging by fine dirt particles, so that when it rains, water pressure behind the new wall is not allowed to build up & exert excessive pressure on the wall---water pressure buildup in rainy weather is the major reason that exterior stone retaining walls fail within a few years.

This type of wall would be your best chance of constructing such a structure as you describe in your post---but I wonder why you need such a wall to such length----could you post some photos of your yard---are you on a hill or is your yard completely hilly???

Before you start the project, Spruce makes a good suggestion that you have a few consultants over to look at the work & suggest solutions & plans that you may not have even thought of & may offer a dollar quote for the work that is less that you imagine---there are stone contractors in this line of work who work exclusively in landscaping mortarless walls that have the expertise & access to low-cost natural stone that may be unobtainable to you---just obtaining the amount of stone building material you need for such a wall can be well out of your reach.

Consult the Yellow Pages under "Stone, natural", "Stone Masons", "landscaping contractors","landscaping consultants"--they will probably all give you a slightly different take on how the job should be tackled.

Google "mortarless natural stone retaining walls" to get a long list of techniques & tips on how to build these walls.

Re: Retaining Wall

What Pelton said plus;

Drylaid (mortar-less) installations take much more skill than concrete re-enforced structures. Do a lot of research and get a warranty that covers several years.

Re: Retaining Wall

Thank you very much for all the information.

The two main reasons for using "cinder" blocks are to match the existing short piece of retaining wall (which is part of the foundation), and to keep costs down.

The yard used to have a big slope down to provide day-light for the basement and being able to walk out. However, the slope made the space unusable, and gave it a feeling of being down and dark. I have already moved all the dirt (by hand), and the area is already much nicer - just need the retaining wall and then install ground cover.

It is unfortunately not practical to split the retaining wall in two terraces, due to the close proximity with the deck.

This is a link to pictures of the construction site


Again, thank you for all the great information.

Re: Retaining Wall

Link not working?????????
Can't open.

Re: Retaining Wall

Sorry for the delay here is the link to pictures

h t t p s://picasaweb.google.com/sara.rasmussen10/RetainingWall?feat=email#

I can not yet post links, so please remove the spaces

Thank you.

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