Fensterbank

Fensterbank is the horizontal ledge at the bottom of a window opening. The term is used in German architecture for both interior and exterior sills, though the exact style and materials vary by climate and construction. An interior Fensterbank often serves as a shelf and a surface for houseplants or ornaments, while exterior versions shed rainwater and protect the wall from moisture.

Materials commonly used for Fensterbänke include wood, stone (such as limestone or granite), concrete, brick, metal alloys, and modern plastics like PVC. Timber sills are typical in older buildings and may require sealing and periodic painting or varnishing. Stone and concrete are favored for exterior use due to durability and weather resistance. In renovations, prefabricated sills or window units may be integrated into the frame.

Design and installation considerations include a slight outward slope to drain water away from the wall and prevent seepage. Exterior sills extend outward beyond the wall face and often feature a drip edge. interior sills are anchored to the window jambs and may be recessed or protruding, depending on window style. The depth and thickness depend on wall construction, window type, and architectural style.

Maintenance and care involve regular cleaning and inspection for rot, cracks, or water damage, with resealing or repainting as needed. Proper drainage and weather sealing are essential to avoid moisture problems and mold, particularly for wooden interior sills and exterior stone or concrete variants.