Driveway using retaining wall to level - Proposed plans

[marty552]

Hi,

I have a sloped front unused garden (excavated to clay) that I'm planning to convert to a driveway. The drop kerb has been approved.

However I would like someone in this field of landscaping/construction to check my plans. I'm not going to hold anyone to their word, I am new to this and I want to know what someone would usually do.

Link: https://ibb.co/P6LGLM4

My main concern currently is the footing requirements, as that's the first step. Basic stats from the link:

- length 5.7m x width 2.7m
- Using hollow concrete blocks 415mm x 215mm x 215mm
- Footings 280mm depth x 330 width
- Using 12mm rebar in the footings to line up with holes in hollow bricks, which I'll then fill with concrete
- I will terrace the clay earth to reduce pressure on wall and 'slippage'
- I can create weep holes at the bottom end of the retaining wall by either not filling in cement between two blocks, or using hole saw on a few bricks (not sure how many weep holes needed)

I'm confident in making the wall itself, but not sure about footings (most important part I think).

Any other advice would be welcome.

Thanks.

[digerjones]

The rule of thumb with retaining wall footings is, you need a toe going back under the material your holding back. There's a calculation somewhere, where the toe is a % of the hight of wall. Like hight of wall =1m toe on footing =750mm.
Behind wall you normally lay perforated land drain wrapped in geo textile material. Back filled with pea gravel.
Regarding putting clay back and whacking, that wouldn't be a recommended method. Back fill with type 1 and whack in 100mm layers.