Hi all.
I have not long purchased a house with a decent size back garden, however the house sits below the level of the garden ( Back door approx 6ft below top of garden) The garden is in an L shape ( across the back and down the side of the house) and slopes. There is a walkway down the side of to the house approx 700mm wide between the garden and the house leading onto a patio area, back door, Patio doors, etc. We would like to build a retaining wall out of poured concrete, approx 6ft high for about 12ft then turn It down the side of the house, drop the level to 4ft and 20ft run. The walk way will be widened (Double the width). The garden is to have 2 tiers the tier that runs down the side of the house being about 2 or 3 ft lower and both tiers levelled. My question is how deep and how thick do we need to make the concrete walls?