What is the minimum tread depth for rectangular treads in stairways?

The correct minimum tread depth for rectangular treads in stairways is indeed 11 inches. This measurement is established to ensure safety and accessibility for users. A tread depth of 11 inches provides a sufficient area for foot placement, reducing the risk of slipping or missing a step when ascending or descending stairs. It also aids in preventing fatigue, as a deeper tread allows more comfortable foot positioning, particularly in commercial buildings where high foot traffic is common.

Understanding building codes is crucial for maintaining safety standards in public spaces. The minimum tread depth is part of guidelines that help architects and builders create stairways that accommodate a diverse range of users, including those who may have difficulty navigating stairs. Proper tread depth is a critical element in stair design, as it influences usability and safety.