What is the standard range for the width of the nosing on a stair tread?

The standard range for the width of the nosing on a stair tread is typically 1" to 1 ½". This dimension is established to ensure that the nosing provides adequate footing and enhances safety by allowing users a secure edge to step on. Nosing is the part of the stair tread that extends beyond the riser and is especially crucial in preventing slips and falls, as it helps define the edge of the tread clearly.

A nosing that falls within this range helps provide enough overhang to give guidance to individuals using the stairs, ensuring visibility and making the step easily recognizable. This is particularly important for safety compliance in various building codes and regulations which aim to create stairs that are safe and practical for all users.

While other ranges might be considered for specialized applications or design aesthetics, the 1" to 1 ½" measurement strikes a balance between safety, comfort, and practicality in general construction.