Dakkapel

Dakkapel is the Dutch term for a dormer window that projects from a sloping roof to create additional living space and daylight in an upper room or attic. Unlike a small roof window, a dakkapel extends beyond the roof plane with vertical side walls and a distinct front, which provides additional headroom and a more regular room shape inside. It is commonly used to transform an attic into a usable room and to improve natural light and ventilation.

Most dakkapellen are built on existing pitched roofs and can have a rectangular, curved, or gabled front. They are typically constructed with a timber or metal frame and finished on the exterior with brick, plaster, timber cladding, or plastic. Windows are usually larger than standard roof windows and may be casement or tilt-and-turn. Interiors are often finished with plaster walls and insulation, turning an attic into a small, habitable space such as a bedroom, study, or bathroom.

Materials and design vary across regions and preferences. Dakkapellen can be made with masonry bases or entirely in timber, and the exterior finish is chosen to match the house. Energy performance depends on insulation, glazing, and integration with the existing roof structure. Aesthetics also play a role, as the dormer affects the roofline and the overall appearance of the building.

Regulation and planning considerations differ by country and municipality. In the Netherlands and Belgium, building a dakkapel may require a building permit or fall under permitted development rules depending on size, location, and local planning regulations. It must comply with local building codes, fire safety, and structural standards, and may involve considerations about drainage, waterproofing, and maintenance.