This proposal for the new Guggenheim museum in Helsinki uses digital methodologies to design a carbon-negative building which is largely made of recycled and low-grade timber. The ground floor of the museum is completely transparent and accessible via multiple entries; the museum has the possibility to run different security regimes, shifting ticket control and bag check to the first floor, which would effectively turn the ground floor into a generous, freely accessible civic space, a meeting ground for the city of Helsinki. Instead of a surface, the roof is conceived as a volume, and acts structurally as a beam - similar to airplane structures. The lightweight stressed skin structure makes use of low-grade and recycled timber, which would otherwise not be suited for the construction industry and be used as fuel. To prevent difficult joints or massive customization of joints, there is a high degree of repetition in the structure. Slender timber posts are organized in clusters to support the roof construction, the density of clusters being proportional to adjacent span lengths. The museum floors are designed as Brettstapel timber composite floors, which have excellent thermal properties and are largely fabricated off-site. Through the combined use of highly sustainable Brettstapel floors, glulam beams and a timber stressed skin of low-grade and recycled wood, the new Guggenheim museum would be carbon-negative – resulting in a minimal life cycle impact.