I am in the process of draining my house and now need to redo two retaining walls for the staircase that leads down to the basement, as the previous construction was too low. The staircase will go straight out from the house with a retaining wall on each side of the staircase. The wall will be about 2.4 meters long and about 1.7 meters high. I was thinking of casting a footing directly on the rock and then building with Leca blocks. What do you think? Will it work with Leca blocks or do I need to cast in concrete? Another solution I considered was hollow blocks where I reinforce and cast in them. I want to try to avoid casting because I would need a pump truck for that. What do those of you in the know say? Will it work with Leca blocks?