Building a Retaining Wall on a Slope by Stepping Up the Base Course

Walls built on a sloping grade require a stepped base.

Begin excavation at the lowest point and dig a level trench into the slope until it is deep enough to accommodate the base material and one entire block.
At this point step up the height of one block, and begin a new section of base trench.
Continue to step up as needed to top of slope.
Always bury at least one full unit at each step.