The minimum exterior expansion joint width for joints 12 foot on center is:

The minimum exterior expansion joint width for joints spaced 12 feet on center is specified to be 3/8 inch. This width is critical because it allows for the necessary movement that occurs due to temperature changes, settling of the building, and other factors that can cause the materials to expand and contract.

Using a width of 3/8 inch ensures that there is enough space to accommodate these movements without leading to damage in the flooring material, such as cracking or warping. It reflects the best practices in construction, emphasizing durability and the longevity of the flooring system. Different dimensions for expansion joints are defined based on specific spacing and anticipated movement, and 3/8 inch represents a balance between structural integrity and functional flexibility for a spacing of 12 feet. This standard is consistent with industry guidelines, ensuring that interior and exterior flooring installations can withstand environmental stresses effectively.