Retaining Wall Block Calculator

This calculator sizes a segmental retaining wall: block count per course, total courses, total blocks, cap units, backfill gravel, and optional geogrid reinforcement area. Wall Height governs Total Courses -- and through it, Total Blocks and Backfill Gravel -- since a taller wall simply stacks more courses at the same Block Height, while Wall Length governs Blocks Per Row and Cap Units, since a longer run needs more block face length at the same Block Length. Setback per Course has a slot on the form for describing the wall's batter, the intentional backward lean each course takes, but nothing downstream reads that number: block count, backfill volume, and geogrid area come out identical no matter what setback figure is entered.

Geogrid Required works as a simple on/off toggle -- left off, Geogrid Area stays zero and the reinforcement math never runs; turned on, it adds layers at every other course, reaching back 60% of Wall Height from the wall face, without touching the block or backfill numbers at all. Backfill Gravel itself assumes a drainage zone behind the wall sized at 60% of Wall Height for its width. Segmental walls taller than roughly 4 feet typically cross into engineered-design and permit territory -- this tool is a material takeoff aid for planning, not an engineering sign-off.