A banula is a small window or opening in a wall, originally intended for ventilation or light admission. It is found primarily in historic or ecclesiastical architecture.
Origin and context
The term banula originates from the medieval building tradition and refers to a small, often irregularly shaped opening in a thick stone wall. In early church architecture, banulas were incorporated to admit a minimal amount of daylight and fresh air into the building without compromising the structural strength of the wall.
The openings were typically too small to function as a full window. They were not glazed but left open or covered with a shutter or a piece of cloth.
Function
The banula served two main purposes:
- Ventilation — In thick stone walls where regular windows were absent, the banula provided limited air circulation. This was important in spaces where moisture or heat could accumulate, such as crypts, cellars and attic spaces of churches.
- Light admission — The small opening allowed a beam of daylight into otherwise dark spaces. In churches, this could serve a symbolic function, with the light carrying religious significance.
Relationship to other openings
The banula shares similarities with other small wall openings in historic architecture:
- The sound opening in bell towers, designed to allow the sound of the bells to project outward.
- The niche, a recess in the wall used for storage or for displaying statues.
- The light opening or light slit in fortifications and castles, which served both illumination and defence.
Identification
Banulas are recognisable by their small dimensions, usually no larger than 20 by 30 centimetres. They often have an irregular or rounded shape and are set deep into the wall due to the considerable wall thickness of historic buildings. During restoration, banulas are carefully preserved as a characteristic element of the original building period.
Related terms
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