Garden wall made of formwork stones for earth embankment

Hi,

we are planning to equip our property facing the turning circle with a garden wall. Against this garden wall, we want to mound up a embankment from the inside of the property and then plant it as a flowering/wild hedge. The whole thing should then serve as a long-term privacy screen. The embankment itself should be about 1.10 meters high and 2/3 meters wide.

The wall should have a length of 28 meters and a height above ground of 1.25 meters. As a foundation, I have planned 10 cm of gravel and 3 rows of 24cm formwork blocks. Every 6 meters, the formwork stone foundation should get cantilevers under the future embankment, forming basically an L shape. The foundation should be reinforced horizontally in the 1st and 3rd rows with 8 mm rebar and horizontally toward the embankment every 50 cm with 10 mm rebar. On top of this, 5 rows of 17.5 cm formwork blocks are to be laid. These should also be reinforced horizontally in the 2nd and 4th rows with 8 mm rebar and horizontally toward the embankment every 50 cm with 10 mm rebar. The horizontal reinforcement then goes through all 8 rows, with a distance from the ground. The top row of the formwork blocks should then only be filled about 1/3 with concrete in order to plant on it later. The embankment should also only be piled up to the bottom edge of the upper stone row there. Toward the embankment, the wall should be sealed with a bitumen coating and dimpled membrane.

As far as possible, I have informed myself on this topic, also here in the forum. In exchange with other builders in the neighborhood, I was asked if I am preparing for a war, keyword tank barrier. In conclusion, I am not sure whether the whole thing is somewhat overdimensioned, regarding the foundation and reinforcement. The wall must hold the embankment, but this will be mounded shallowly and planted; no additional pressure is exerted on it.

Finally, my question: is the construction okay as it is or maybe overdimensioned? Does anyone have suggestions or tips?

Many thanks
Marc

We are planning to equip our property at the front towards the cul-de-sac with a garden wall.
Against this garden wall, on the inside of the property, we want to pile up a berm and then plant it as a flowering/wild hedge.

So basically a Frisian berm that appears street-side in a wall look.

The wall should have a length of 28 meters and a height, above ground, of 1.25 meters.

Even assuming that "above ground" only means the height above the original terrain, I would consider this a borderline structure requiring permission.

Ask a structural engineer.

I don’t know your heights but with 1.2m wall plus 1.1m embankment you will have to go through an approval process anyway.
I would also take the (still) smiling comments of the neighbors a bit more seriously.

I also built a wall in the same dimension to catch the slope. Also formwork stones, 8mm steel inside, and concrete.

So basically a Frisian earth wall that appears on the street side in a wall look.

Even assuming that "above ground" only refers to the height above the original terrain, I would consider that a borderline structure requiring approval.

Exactly, similar to a Frisian earth wall, just in a wall look.
Yes, original terrain meaning 1.25m above the asphalt surface of the turning area, equivalent to my original property height.

Ask a structural engineer.

I don’t know your heights but with 1.2m wall plus 1.1m earth wall you will have an approval process anyway.
I would also take the (still) smiling comments of the neighbors a bit more seriously.

As far as approval etc. is concerned, that is not an issue at least for Lower Saxony.
It is to be considered a boundary wall and as long as I don’t exceed 2m no special statics or building permit is required.
Also from the municipal side, since the wall does not border any neighbor here but only the traffic area, there are no objections. It is also implemented this way in other places in our development areas, only there no earth wall leans against the wall, but the properties were completely filled up.
And I also don't have to worry about the neighbors, as no one is directly affected here, and the development plan allows it; it is a mixed-use area.
So there are no other restrictive external factors, except the execution of the structure.