What is the maximum projection of beams below the ceiling for it to be treated as a smooth ceiling?

A ceiling is considered smooth when projections such as beams do not disrupt its appearance or functionality. The maximum allowed projection of beams below the ceiling for the ceiling to still be classified as smooth is 4 inches. This specification is important in various building codes and standards, particularly in creating a safe and visually appealing environment. When the projection exceeds this limit, it may affect the aesthetic quality of the ceiling and potentially create hazards, such as reducing headroom or obstructing fixtures. Hence, adhering to the 4-inch maximum ensures that the ceiling maintains its functional and aesthetic integrity, thereby supporting architectural and safety standards in building design.