How wide should the mortar joints be at a minimum?

The minimum width for mortar joints is typically set at 1/4 inch. This standard is established to ensure proper bonding between the masonry units and the mortar, allowing for some movement and flexibility in the structure. A joint that is too narrow may not accommodate the necessary expansion and contraction that can occur due to temperature changes or settling, potentially leading to cracking or failure of the masonry. On the other hand, a mortar joint that is too wide can result in increased mortar usage and may compromise the strength and aesthetic appearance of the masonry work. By adhering to the 1/4 inch specification, masons can maintain not only the integrity of the structure but also achieve a neat and uniform appearance across the masonry work. This width strikes a balance between structural performance and efficiency in material use.