Concrete block walls vs poured walls
A concrete block wall is stacked masonry. Quantity comes from the wall face divided by each unit’s nominal face, not from a solid volume of concrete. If you need cubic yards of ready-mix for a solid wall, use the concrete wall calculator instead.
How this calculator differs
It uses the same engine as the cinder block calculator because modern “cinder” blocks sold at yards are usually concrete masonry units. The emphasis here is wall layout: multiple sections, openings, and modular 8×16 in faces used in concrete masonry construction. For how units, mortar, and grout work together on a jobsite, see the CMHA concrete masonry construction overview (opens in a new tab).
Nominal vs actual size
An 8×8×16 in concrete block is typically manufactured about 3/8 in short in each modular direction so a mortar joint completes the 8 in grid. Counting with nominal face dimensions is the usual estimating method for running bond walls.
Looking for the full estimator with wall diagram and openings? Use the cinder block calculator.