A curious choice for a museum extension shaped like a squashed sphere: ceramics. The architects designing new space for a Dutch museum made a conscious decision to use sky-coloured tiles to cover their rounded creation. The effect is appealingly original, as well as being remarkably sensible.

The ‘De Fundatie’ (The Foundation) museum in Zwolle, NL, required an addition as a result to a very successful exhibition several years ago. Architects Bierman Henket convinced the directors not to expand beneath or next to the building but to allow new growth on top of the existing design.

The rugby-ball shaped extension houses two floors of exhibition space of about 1000 m2. Its flowing spaces indicate the designers’ idea of art in a contemporary setting. This art is illuminated by a large glass cut-out in one side. Structurally, the ball itself is a rounded box with steel framing for strength and solidness. All this stands on eight steel columns which pierce the old building.

This gave the architects the freedom to rethink the way an extension should perform. The ‘cloud’ was designed to be a separate, singular entity. Further requirements included abstract ideas – graceful aging, vivid materialisation and the illusion of a spotless façade.

Researching different alternatives brought the designers to Dutch ceramics legends Tichelaar. They were able to produce two different tiles, both wedge-shaped and glazed. To cover the curved area, different sizes were required: 200x200mm and 100x100mm.

These are arranged in what the architects call a ‘quasi-random’ pattern, to maximise efficiency. Occasional flat tiles fill in holes. All tiles are hand-glazed in a progressive hue from white to blue.

The 3D shaping mean that rainwater runs off without leaving discernable traces, while the colouring ensures that smudges are harder to spot. Together, the effect is a shimmering ball of tiles that reflects the diverse local weather conditions. The ceramic cloud sits proudly on top of the original, early 19^th century building – and it’s well worth a visit.

Photos by Rob Hoekstra.