Most concrete masonry units are called ___, which have the familiar shape of a CMU.

Most concrete masonry units are called ___, which have the familiar shape of a CMU.

• A. Jambs
• B. Headers
• C. Columns
• D. Stretchers

Answer: (D)

Stretchers describe the blocks used most often in CMU walls. They are laid so the long, rectangular face is visible on the wall, which gives you the familiar CMU shape. If a block is turned so the short end faces outward, that is a header, used to tie wythes. Jambs are blocks used around openings like doors and windows, and columns refer to vertical structural members, not the typical wall surface. So the common CMU units you see forming most walls are stretchers.

Stretchers describe the blocks used most often in CMU walls. They are laid so the long, rectangular face is visible on the wall, which gives you the familiar CMU shape. If a block is turned so the short end faces outward, that is a header, used to tie wythes. Jambs are blocks used around openings like doors and windows, and columns refer to vertical structural members, not the typical wall surface. So the common CMU units you see forming most walls are stretchers.