With topping up, you add an extra floor on top of an existing building. This creates new living space, often in inner-city areas where space is scarce. For property owners and developers, topping up is a smart way to contribute to the housing challenge while increasing the value of their property. For private homeowners, it also has its advantages: with a roof extension, you create an extra living level in your own home — for a more spacious living room, an additional bedroom, or a comfortable home office.

How this works in practice is shown by a home in Watergraafsmeer: a ground-floor 1930s apartment, redeveloped into a future-proof family home. The building has the character of Amsterdam's early garden villages. This means it is a wider home with a deep garden, which allowed us to plan the redevelopment and extension without a building permit.

The home has been fully renovated and expanded, making it future-proof for a family with two children. Kentie Architecten developed a design vision that creates a balance between maximum expansion and the preservation of spatial quality — both indoors and outdoors. The client envisioned a contemporary look, with abundant natural light, a calm atmosphere, and a child- friendly which means a robust finish.

The extension makes use of the maximum permit-free possibilities and aligns in shape with the existing rear facade, built in sections of four meters. A contrasting design with a modern appearance and a slim roof edge was chosen. The new layout created a spacious kitchen-living area and a third bedroom, making clever use of light and sightlines. Additional space was also made for an ensuite bathroom and walk-in closet, giving the home an extra sense of luxury.