The Spore Initiative is a foundation dedicated to uniting sustainability and culture. The team designing the foundation’s new center for Earth-centric, global environmental projects—the Spore Initiative House—was challenged to also do the same at the level of building culture in the load-bearing structure. Its address in Berlin is Hermannstrasse 86, near the U8 subway line, and it is located next to a landmarked beacon tower from the disused Berlin-Tempelhof airport as well as a former cemetery with immovable graves, a landmarked gate, and a boundary wall worthy of preservation.

Plant spores serve as the starting point for an emergent, seamless organic structure designed to achieve maximum results with minimal material input. This is the guiding principle for the load-bearing structure, which was developed during the competition phase with the aim of providing monolithic support that offers the greatest possible flexibility of use. Three other aspects were also crucial to the project: the design of load-bearing elements with minimal cross sections, the use of recycled clinker for the facade that wraps around the second floor and reddish recycled-aggregate concrete at the ground floor level, and the reuse of construction waste for secondary load-bearing elements.

A key architectural element is the striking “Spore ceiling.” Through iterative processes, parametric simulations of computer-based 3D models were used to translate the principal stress trajectories of the slab load curves into a concrete rib configuration. The result was a ribbed slab of exposed concrete that uses extremely little material and spans up to 12 meters. In order to keep the relatively high fabrication costs within budget, the formwork production was also developed from the 3D model and translated into cutting and construction templates for the formwork contractor.

An ingeniously balanced structural system combines the organic-looking ceiling slab on the ground floor and prestressed shear walls distributed over three floors to achieve three goals at once: create the column-free museum spaces on the second floor, construct the column-free ground floor, and solve the foundation problem posed by the old masonry subway tunnel beneath Hermannstraße. This is remarkable given the high level of material reuse, high material efficiency, and minimized raw material consumption. Alongside all the landmarked buildings, Spore Initiative definitely has the potential to achieve this status for itself in the future, thanks to its efficient, ecologically implemented, and materially optimized load-bearing structure.