The listed castle in the centre of Sint-Gillis-Waas had long been too small as a town hall. In addition, the caretaker occupied a part of the building. That is why, a few decades ago, a new building was erected a dozen metres to the left of it, with a glass corridor between them. Unfortunately, the intervention proved unsuccessful in both aesthetic and organizational terms. A new design by Els Claessens and Tania Vandenbussche (ectv) has healed all wounds.

ECTV has placed an unusual structure directly behind the little castle. From the outside, it looks like an irregular two-storey hexagon. The front façade, which faces the little castle, and the rear façade are shorter than the others. A glass passageway, whose walls lie in line with the side façades of the new building, connects it to the little castle and also serves as the main entrance.