The paramount design task for the soft-water bath was the ribbed timber shell hanging from five tree-like branched supports spanning the given layout. The shell facilitated the free spanning of all functional realms as well as maintaining the buoyancy of the layout and continuating it into the contours of the roof. A prolonged process to coordinate the functional specifications of the layout and the structural requirements of the roof construction ensued. Focus was on an appropriate design for the steel parts and aluminium castings for the supports of the roof both in the surround and the centre, as well as for the tripartite concrete anchoring along the facade.