The ideal height of a shower seat is one that makes the seat easy to use, even for people who have limited mobility, and that ideal height is specified in federal guidelines for accessible building construction.
The Americans with Disabilities Act establishes guidelines for building design with the goal of making all public facilities accessible to everyone regardless of physical limitations. The ADA rules apply to public and commercial buildings, but the act's guidelines also provide valuable guidance to private or residential builders who want their buildings to be optimally accessible.
The ADA provides detailed requirements for shower seat design and placement, including clearances between the seat and the shower opening, between the seat and the shower wall. The requirement for seat height, however, is very simple: The top of the seat must be a minimum of 17 inches and a maximum of 19 inches above the shower floor.
Building Code Requirements
Private construction is governed by building codes that are maintained and enforced by local building authorities. Although codes vary from locality to locality, most local building codes are based on the International Residential Code, a standard code developed by the International Code Council.
Like the ADA, the IRC gives recommendations for shower seat placement that are primarily concerned with clearances around the seat and do not specify seat height. In the absence of specific code requirements, the National Kitchen and Bath Association echoes the ADA's recommendation of a seat height between 17 and 19 inches. This recommendation applies to all types of shower seats, including folding seats, removable seats and permanently installed bench seats.