What is the minimum size waste outlet for a bathtub?

The minimum size waste outlet for a bathtub is 1-1/2 inches. This size is important because it ensures that waste water can drain efficiently without risk of clogging. Bathtubs typically hold a significant volume of water, and having a larger drain helps to prevent the accumulation of water and allows for quicker drainage, particularly when multiple fixtures might be in use simultaneously or when water is being drained quickly. The plumbing code specifies this size to maintain proper flow rates and avoid potential drainage issues that could arise from smaller outlet sizes. Moreover, using the correct size also helps in meeting building codes and ensuring compliance with plumbing standards, which is crucial for maintaining safety and functionality in plumbing systems.