How are units of CMUs estimated for masonry work?

Estimating units of Concrete Masonry Units (CMUs) for masonry work is typically done per course, or one row, as this approach reflects the actual construction process. Masonry is generally laid in horizontal rows, with each course composed of a specific number of blocks. By estimating per course, it's possible to accurately determine how many blocks are needed for each horizontal layer and account for any adjustments in mortar joints or cuts that may be necessary.

This method is practical because it aligns with how masonry is constructed on-site, allowing for better quantities planning based on the height and configuration of the wall being built. Each course builds directly on the one below it, making it a straightforward approach for estimators and masons to visualize the number of blocks required and to adjust as needed based on wall dimensions.

Other estimation methods, such as calculating per square foot or per wall area, lack the specificity that course measurement provides and can lead to inaccuracies due to factors like block size and joint spacing. Estimating per block, while it gives a basic count, may not effectively account for the layout and bonding patterns needed in actual masonry work, which can influence the total number of blocks required.