Retaining wall with huge granite block - Foundation issues

[jaysettpav]

Forgive me for sending the previous post. I was searching previous posts with default setting which seems to be limited to one month old posts.

In my previous post, I mentioned about the fall away from the house. when slope is towards the house. If I go with this option, there will be about 30cm or so of difference in height so I think a retaining wall is necessary. I am not a brick layer so I thought about flags on sides but this requires the use of concrete so I thought about placing large blocks (1m long, 40cm high and 30cm wide). I thought this can function as a sitting area as well. I was wondering whether the foundations, namely the sub-base and bedding should be different to the rest of the patio? Driveways are designed to support cars with a much smaller surface area (tyres), I thought sub-base which is thick enough for a driveway would be adequate.

The other issue is perhaps the stability of it. I cannot imagine someone kicking it over but as a precaution, should it lean on to the soil rather than rest vertically?

[Tony McC]

Blocks of that size definitely need a concrete foundation otherwise they *will* settle.