The roof is designed as a self-supporting, timber shell made of cross-laminated timber panels nailed together. These timber panels were malleable enough to be able to be bowed into the desired shape on site. The panels of the first layer were curved over a formwork, while the panels of the second and third layer were nailed over it and rotated by 60°. The third layer already had the 271 curved cut-out shapes of the openings, which were later cut into the roof on site. Constructing the roof was like building an ark. Rather than high tech machinery, handcraft and sheer human power were needed to realise the unconventional shape.