Floor-to-floor height

Floor-to-floor height describes the total vertical distance between two storeys, usually measured from the top of one slab to the top of the next. It includes the slab itself, the screed and floor finish, and any suspended ceiling and service zone. What people actually feel is the clear ceiling height left over once all of those are subtracted. The Turkish term is kat yüksekliği.

What it affects

Floor-to-floor height directly sets the overall building height, the number of storeys, the number of stair risers, facade proportions and how generous the interior feels. Tall rooms feel brighter and airier, and daylight reaches deeper into the plan. Every extra centimetre, however, costs more in facade area, materials and heated volume. Offices and commercial buildings need more height than housing because of their denser services.

Regulations and the design process

In Turkey, minimum clear heights and limits on building height are set by zoning regulations, the zoning plan and its plan notes, and they vary by use and location. Floor-to-floor height should therefore be fixed at the very start, together with the structural and mechanical engineers. Changing it later ripples through everything from the stairs to the facade.

In visualisation, the wrong height ruins the sense of scale. Modelling ceiling heights at their true value in interior renders keeps furniture and human figures in believable proportion.