puolitasoa

Puolitaso is a Finnish architectural term describing a half-story, an intermediate floor located between two main levels of a building. It is not a full storey; the height is typically reduced and access is usually via stairs or a ladder. The purpose is to create additional usable space within a limited vertical height.

The space is often used as a sleeping loft, a small living area, a work nook, or for storage. In architectural drawings, a puolitaso is depicted as a separate level with its own floor line, and it may be open to the lower level or enclosed behind rails or walls. The design can affect daylight, acoustics, and safety considerations, and building regulations may impose requirements for headroom, guard rails, and means of egress.

The term is commonly used in Finland and is sometimes translated as mezzanine or half-storey in English, though practical implementations can differ from a traditional mezzanine depending on height, access, and local codes. In residential architecture, puolitaso is frequent in compact city apartments, renovations of old industrial buildings, and other spaces where adding a full extra floor would be impractical.

See also: mezzanine, loft, parvi, half-storey.