What is a primary reason for specifying floor-mounted water closets?

Specifying floor-mounted water closets primarily relates to their installation requirements and how they might affect plumbing layout. One of the significant advantages of floor-mounted water closets is that they typically require a smaller plumbing chase size compared to wall-mounted models. Since floor-mounted units rely on a straightforward floor drain and can be installed directly over the plumbing without requiring complicated wall modifications, they allow for more compact plumbing systems. This can simplify construction and reduce costs, especially in tight spaces or when retrofitting existing buildings.

Although durability might be a consideration, as floor-mounted units can withstand more wear and tear, and while aesthetics and water efficiency are important factors in design, they do not capture the core reason for choosing a floor-mounted design over alternatives. The efficient use of space in plumbing configuration is a key practical aspect of selecting water closet types in architectural planning.