invisible extension overlooking nature



At the Nigerian Embassy in The Hague, we designed an extension to the official residence for conference rooms and guest areas.

To preserve the detached nature of the villa and the beautiful views of the pond and gardens, we exploited the extension at level -1. By placing the extension in earthworks, the ground appears to roll smoothly, as if the extension is built underground. This can be built above ground within a closed soil balance and the view from the villa is undisturbed.

By keeping to the -1 level the extension connects snugly to the villa. The extension has daylight on several sides and opens to a wide area, providing a vista over the pond and gardens. This will be a strong outside-inside experience and creates the visual impression that the spatial limits are exceeded.

The roof and two walls are covered with earth and vegetation, thus a high isolation factor is created. In addition, this creates double land use; firstly for the conference and guest rooms and secondly, the ’roof’ may used as a terrace for relaxation.

Whether the pond could be used for heating and cooling the building surface areas is being investigated. Through the optimal use of daylight, relatively little additional lighting is required. This action, together with energy-efficient solar panels on the roof of the residence, can realize a sustainable energy generation source.




Handing over


Project type

exterior and interior existing and new building


100-500 m2