Abstract: A masonry unit for constructing a wall is disclosed. The masonry unit includes at least three substantially vertical parallel partitions. Each of the partitions connects to an adjacent partition by a web thereby defining a pair of oppositely-facing open-ended recesses on either side of the web. Each of the webs connecting the partitions is offset from any adjacent webs in the masonry unit. A plurality of separated continuous vertical cavities extending through multiple layers of stacked masonry units are formed within the wall when positioning the multiple layers of stacked masonry units on top of each other in a horizontally offset and vertically inverted manner.