ᐅ Frost-Protected Shallow Foundation for a Retaining Wall on a Slope

Hello,

a slope is going to be retained by a wall. The wall will be a maximum of 80 cm (31 inches) high at its tallest point. (Hollow concrete blocks filled with concrete).

Would you always recommend a gravel layer in the foundation as the first layer, or simply pour a strip footing about 20 cm (8 inches) deep directly into the ground?

Thank you

Should foundations not be set 80cm (31 inches) below the frost line?

Hmm, that’s why I’m asking the community.

I don’t even want to ask what your planner thinks about this.

Supporting a slope is a delicate matter and should be left to professionals.

We are now having our slopes supported. L-shaped concrete blocks up to 180cm (6 feet) high will be used. No foundation is required for these. We initially wanted to use these hollow concrete blocks as well, but as ypg already mentioned, the concrete contractor wanted to install an 80cm (2.5 feet) frost-protected foundation underneath.

Kisska86 schrieb:
We are now having our slopes supported. L-shaped concrete blocks up to 180cm (6 feet) high will be used. No foundation is needed for these. Initially, we wanted to use these hollow concrete blocks, but the concrete contractor insisted on an 80cm (2.6 feet) frost-protected foundation underneath, as ypg already mentioned.

You are not installing a foundation? We received these "thick ones" up to 140cm (4.6 feet) high. First, a layer of gravel was laid, followed by a few centimeters (inches) of lean concrete on which the L-shaped block was placed.
We didn’t handle the details ourselves (so I don’t know how much gravel and concrete were used), as this was work the supplier was responsible for, and we weren’t closely involved.