Gravity wall

[1983]

Hi all.
i'm looking for some advice and you experience of gravity wall blocks. I'm looking to build a retaining wall at around 1.2m in height in my garden. We've had a dig and still have black Earth to a depth of 1.5m from the lowest level. It looks like it might go a lot deeper. Our builder was wanting the found dug down to were the earth stops as origional plan was to construct it out of blocks.
Question what kind of found does the gravity system use and how good are these systems?
Tia.

 

[PaulJR]

Your builder was telling you the truth, you need to get below any sort of topsoil. A gravity retaining wall needs a solid base, so a concrete footing is as good as any to ensure local settlement will not cause a failure. Whichever system you are using the manufacturer will have guidelines to follow.

Ensure you have a good drainage system behind the wall that can discharge any groundwater, fin drains etc, also install weep holes higher up to show if there is a water build up before it becomes critical and collapses you wall.