Concrete Masonry Units (CMUs) are manufactured in a variety of sizes. They are identified by their depth – i.e. the thickness of the wall they create. For instance, a 6" CMU is nominally 6" deep while a 10" CMU is nominally 10" deep.What is a 6 CMU block?
Concrete Masonry Units (CMU), or Concrete Blocks, come in a variety of sizes. CMUs are identified by their depth - i.e. the thickness of the wall they create. For instance, a 6 CMU is nominally 6 deep. As with brick, CMUs have actual dimensions and nominal dimensions.What is the difference between a 6 and 10 CMU?
For instance, a 6" CMU is nominally 6" deep while a 10" CMU is nominally 10" deep. Concrete blocks also come in half-sizes, which are helpful in reducing the need to cut blocks in the field at corners or the end of walls.What is the size of a CMU mortar joint?
Typical CMU mortar joints are 3/8". The nominal dimension works within the 4" grid that other construction materials follow. The graphic below shows the difference between nominal and actual sizes.