Temporary Building Zurich Opera House

The limited period for which it will be used and the building’s prominent location in a setting of historical importance, beside the lake and on Sechseläutenplatz, creates a complex context for the construction and design of the ZOTB (Zurich Opera Temporary Building). On the one hand the intention is that the temporary nature of the project should be evident, and the modular timber construction should be reusable elsewhere in accordance with the principles of the circular economy, while on the other hand it must respond to the urban planning situation at this location. The basic geometry is regular and relates to the main geometry of the Opera House. The single-storey ZOTB is understood as a pavilion-like roof-top addition and develops an individual architectural language with inclined walls and a striking roof shape. The short ends respond to the axial symmetry of the facades of the existing building and give the ZOTB a distinctive elegant silhouette. The brise soleil that is integrated in the volume strengthens the two long facades and allows the fenestration to recede in a shadow joint. The technical infrastructure has been designed with great architectural care and integrates the existing chimney stacks in an entirely natural way, while the two PV plants rest on the two sloping roof planes. The bitumen sheeting with slate chip finish that is used as the roofing material continues over the edges and in terms of both colour and material responds to the nearby historic rooftops. In contrast the short end facades and long facades have a painted wooden cladding. Thanks to the care with which they are detailed the simple and ‘poor’ materials used do not seem cheap, they will acquire a patina in the course of time and are combined in a way that is appropriate to the pavilion’s temporary character.

To minimise the load on the ceiling slab of the existing extension building, the ZOTB is timber built. Given that it will later be used at a different location it is a self-contained building. The timber components are designed as large as possible and are easily demountable. The separate floor is a ribbed slab with structurally effective planking on top. The external walls are timber frame constructions, with some bracing walls built of cross-laminated timber. As timber construction means a shorter building period the extension of the existing lift and smoke and heat extraction shaft is also built in timber. The primary structure of the roof consists of a regular grid of purlins and rafters designed using a modular construction method. The clarity of this structure means that there are practically no loadbearing internal walls in the interior of the building, which allows the floorplan to be used flexibly.