What does the term 'plumb' refer to in masonry?

In masonry, the term 'plumb' refers specifically to the vertical alignment of masonry elements. Achieving plumb ensures that walls, columns, and other vertical structures are straight and upright, maintaining structural integrity and aesthetic appeal. This concept is crucial in construction because even a minor deviation from plumb can lead to issues such as uneven loads, compromised stability, or visual defects.

To check for plumb, masonry workers typically use a plumb line, which consists of a weight suspended from a string to indicate a true vertical line, or a spirit level designed to indicate vertical alignment. Ensuring that structures are plumb is a fundamental practice in masonry to ensure the overall quality and longevity of the construction.