Final answer:
The leading edge (nosings) of stair treads should not project more than 1¼ inches beyond the tread below according to building construction codes and regulations.
Step-by-step explanation:
The answer to your question lies in building construction codes and regulations. The leading edge, or nosings, of stair treads should not project more than 1 ¼ inches beyond the tread below according to the International Building Code (IBC) and other related standards. This measurement helps to ensure safety and prevent accidents by providing a consistent and predictable stair design.
For example, if the nosing of a stair tread extends too far beyond the tread below, it can create a tripping hazard. Additionally, if the nosing is too short, it may offer less support for the foot and increase the risk of falls.
The regulation serves to make sure that the stairs are comfortable and safe to walk on, allowing individuals to navigate them easily and with reduced risks.