tall, the wall above it should be built at least 8 ft. behind it. Stagger the overlaps (at least 4 in. for this Versa-Lok product) and try to keep the butt joint between the retaining wall blocks ...

They are not ideal for tall walls, and should not be used to build walls taller than 4 feet. Note, however, that most jurisdictions require permits and engineering drawings for all retaining walls ...