Concrete block on the retaining wall

The home owner plans on building a 10 by17 shed. One side of the shed will be in the edge of a retaining wall. On this side the plan is to build three concrete blocks for the shed framing to sit on. My concern is that the concrete blocks (like fence post concrete) is too close to the edge. Do you see the supporting issue after years? Maybe there is a lateral force pushing the retaining wall out and eventually collapse and then lose the support to the three blocks?

That soil along the retaining wall will likely be fill dirt. Pour footing for the block piers and you should be good to go.

Yes, it won’t hold up. As said above, ^^^^^^^^^^^^^

Helical piles (screw piles) could work.

https://www.technometalpost.com/en-CA/dealer/techno-metal-post-pei-prince-edward-island-helical-piles/

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https://www.basalite.com/how-tos/how-to-determine-if-you-need-engineer-retaining-wall-design

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I wouldn’t set the shed any closer to the wall than the wall is high, (45 degrees)

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I agree Randy, the retainer blocks in the picture are just gravity-held, I have used those before, and if in a frost zone, the frost pushes them out every year, and if not, the settlement of the dirt is enough to slide them over.

Not to mention the angle of repose…

Manufactured Concrete Dry stacking CMU retaining wall blocks.

The lot soil is prepared by cutting back the soil on a 45° angle. 'I used geo fabric to separate the soil ’ from the, clean washed 3/4" gavel/drainage aggregate used as ‘drainage infill…’

Drainage is required, at the footing when 4 feet tall or more, Weep holes used when no weep tile present which in your case appear to be case.
Last 2 coursed require physical bonding with an approved constructive adhesive.

Personally, I would not build a shed there… It is not a swale.

Manufactured Sheds belong at the back of a yard raised 4" inches from grade, seated on poured/manufactured concrete footing pads to allow for circulation under the shed flooring assembly, not on the side of a home.

My advice is under the presumption the retaining wall is built correctly. Here is a good article about interlocking segmental block retaining walls.

Segmental Retaining Walls - The Concrete Network - The Concrete Network.

Brian, the only interlock those blocks have is a 1/2" lip on the back side to keep them from moving. I would not build anything near them.
I used the same block near my shed last year.

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They are used a lot here in Ga. Thirty foot tall nearby walmart. DOT using then as well. I’m not advocating them, but they seem to perform well when properly designed and installed. Furthermore, the life span of the materials must be a plus.

There are some that look similar but have pins in them. They are quite a bit stronger. Usually on really high stuff I see those.

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Very nice Marcel. Fine example of how to and were to situate sheds.
I think the gravel walkway is perfect as well. Poured concrete settles over time and is an expense to install, repair and remove.
My 2 cents.

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That’s a stone swale with a drainage pipe to handle the neighbors’ water coming off his property.

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Same thing up here at Lowe’s

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I doubt it’s just stacked blocks… they need to re-enforce the soil every so often:

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You think!! LOL

Home Depot told me to put one on top of the other and it’s done :smiley:

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