Wondering if I can have people's thoughts on this retaining wall I'm building. It's a mortared CMU wall with rebar 24" o.c. It's on a slope and it will have a concrete slab and a fence right above the backfill. Above we'll have a combination of foot traffic, outdoor dinning area, outdoor sitting area (with outdoor sectional), etc. Taking that into account, from the drawing does this look like it's a sound and strong enough wall to hold the conditions above? Thanks!!

Drawing of Retaining Wall

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    What are the qualifications of the person that drew it?
    – Ecnerwal
    Commented Apr 10, 2015 at 11:49

2 Answers 2


There are too many unknowns to answer this question. What type of soil is there so a reasonable active pressure, passive pressure, and sliding resistance can be determined? What surcharge is on the 7" slab? How far from the face of slope is the wall located? What is the frost depth? What type of masonry? Grout? Mortar? Reinforcing?

This wall is high enough that a building permit and engineering is required. Do not attempt to design it yourself. Without all the answers to the above questions, I already know whoever drew the detail is not qualified. The vertical reinforcing is too far apart, and it all should be located on the tension face (soil side) of the wall. There is also a need for horizontal reinforcing in the wall, and vertical and horizontal reinforcing in the footing key. Sorry, but spend the extra bucks to get it designed right.


My gut would be happier if the footing went back (right) further, but my gut isn't going to beat a licensed civil engineer, if one designed it.

Retaining walls are trying to overturn (fall down to the left in this picture.) If there's no particular need for it to be vertical, a few degrees of slope into the hill (bottom a bit left, top a bit right) helps to make it more difficult to overturn, too.

I question moving the vertical rebar to the outer side of the core at the second block - rebar holds tension, and the tension is going to be towards the backfill as it tries to push the wall over.

If all the soil to the right is backfill, I'd prefer to see drain lines extending into it. I'd also like to see one at the lower front (left) edge of the footing.

You'll have a fun time compacting that much fill enough that the slab on top isn't sitting over a void after a while, unless you can wait through a winter to help settle it before pouring the slab.

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