What are tail joists used for in framing?

Tail joists play a crucial role in framing by defining the edges of a floor opening. They are typically installed at the ends of a floor frame to support the flooring and ensure structural integrity around openings, such as those for stairwells or chimneys. By providing a stable edge, tail joists help to prevent sagging and maintain the shape of the flooring system. This functionality is essential for both safety and the long-term durability of the building structure.

While vertical support, bridging gaps, and enhancing roof pitch are all important elements in construction, they pertain to different aspects of framing and do not specifically describe the primary function of tail joists. Their main task focuses on delineating openings and supporting the periphery of such areas, which is why defining the edges of a floor opening is the correct classification for their purpose.