Concrete masonry unit CMU
A concrete masonry unit is a standard-sized, pre-cast, concrete rectangular block used in construction. CMU blocks may also incorporate industrial wastes or other types of recycled materials. Breeze blocks (also known as cinder blocks in the US) are created when fly ash is added to the aggregate. The different materials that are incorporated into the mixture can produce various colours.
CMU blocks sometimes have hollow cores to make them lighter and create better insulation when stacked together. The cores can be filled with mortar to create a solid structure.
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