Eight steel columns with their own foundations have been installed straight through the building. The columns bear the weight of the new extension, which contains gallery floors of 1000 m2 in total. This means the extension is structurally and architecturally independent of the old Palace. The extension has been cladded with 55,000 three dimensional ceramic elements produced by ceramics experts Koninklijke Tichelaar in Makkum. The mixed-white-blue glazed 20x20 cm and 10x10 cm tiles together form a nuanced surface which works to blend into the sky in different weather types. On the north side, a façade has been created which provides the two new museum floors with daylight and affords a panoramic view of the city centre from the museum. 

The original central entrance lobby has been continued in the extension in the form of an atrium, bringing the two museum worlds together. A glass lift in the atrium takes visitors to the different floors. The staircases are located away from the centre, on the edges of the various floors. In the oldbuild, they are stately and straight, in the newbuild they are flowing and curved. A glass corridor runs between the existing building and the extension on the interface of new and old. On one side the view is into the atrium, on the other side it is into the city and the bottom of the tiled extension. Museum de Fundatie, whose aim is to present contemporary, modern and older art in a single building, has thus been given a new and completely unique look.