concrete masonry unit
Brick-like concrete blocks laid in masonry, often hollow and sometimes made with coal cinders.
Concrete masonry units are brick-like blocks made of concrete, sometimes mixed with coal cinders. They are often hollow with holes on two sides. Sometimes the holes are configured to form geometric patterns (e.g. pinwheels), and stacked with the holes facing outward. Concrete masonry units are very often painted, unless used as a back or side facade material. Size standards vary by country.
The concrete is formed into individual masonry units rather than a continuous poured wall or a large precast panel. Hollow cores are common, but a hollow form is not required.
Blocks can be arranged with openings exposed to form a decorative pattern. Painting changes their finish without changing their concrete-masonry composition.
