Concrete relief Leonhardstrasse 13
ETH Zurich, Areal Zentrum, Oberer Leonhard. 2007-2015
PROCEDURE
Open two-stage general planning competition, 2007-2008, 1st prize
CUSTOMER
Swiss Confederation
c/o ETH Zurich, Real Estate Infrastructure Division
CONTRACTORS (extended surroundings and conversion of existing building)
Planning consortium PG LEE Conversion:
Architect: Fawad Kazi Architekt GmbH, Zurich
Supporting structure: ACS-Partner AG, Zurich
Building services: Amstein + Walthert AG, Zurich
Site management: Jürg Waldvogel, Architekturbüro, Erlenbach
Excavation pit: Schläpfer & Partner Ingenieurbüro AG, Zurich
Pipelines: Hydraulik AG Ingenieure und Planer, Zurich
Landscape architect: Hager Partner AG, Zurich
Geologist: Gysi Leoni Mader AG, Buchs
TEAM
Fawad Kazi Architekt GmbH:
Project management: Fawad Kazi, Selami Sahin, Philipp Macke
Collaboration: Tommaso Passalacqua, Stefan Günther, Michael Flury, Sebastian Geltz, Benedikt Jäger, Stefano Murialdo, Fabian Markel, Marlen Johne, Nicole Schönfelder, Josephine Kutschbach, Luzius Stiefel, Uwe Gottfried, Daniel Lautenschlager, Pascale Siebers, Luca Riolfo, Manfred Kunz, Laura Perez
ADDRESS
Leonhardstrasse 13, 8006 Zurich, Switzerland
KEY DATA
Floor area: 7 m2
Building volume: 128 m3
Planning: from 2008
Realization: 2010-2015
Construction costs: approx. CHF 1 million
PHOTOS
Georg Aerni, Rolf Steinegger
PUBLICATION
ETH Zurich - Building LEE, ed. Christoph Wieser, Verlag park books, 2015
DESCRIPTION
This project was developed as part of the realization of the LEE building at ETH Zurich.
An originally internal firewall had to be transformed into an external façade as part of the project-related demolition of the adjoining residential building to the north on Leonhardstrasse. Instead of the thermally insulated plaster façade that is usual in such cases, a concrete relief was proposed at an early stage of the project, which was fleshed out during further project planning.
The relief is an inverted cast of the original front façade of the demolished building down to the smallest detail and thus refers to the contextual situation before the construction of the new LEE building. For this purpose, a digital 3D model of the façade was used to produce a latex mold as a formwork insert and the relief was concreted on site in five stages. In order to ensure technical and economic feasibility, the original relief was reduced in depth at a ratio of 1:4. The aim was to achieve maximum precision on the one hand and a light appearance on the other. A self-compacting concrete with appropriate aggregate was chosen for this purpose. The new façade consists of a double-skin, approximately 60 centimeter thick construction with gas concrete thermal insulation and the exposed concrete relief. The particular challenge of the master builder's implementation was that the relief was built on site and therefore without any possible corrective measures.
As the shutters of one of the windows were closed during the entire project planning, this fact was anecdotally recorded in the relief. Due to the elaborate construction and the inherent complexity of the content, the concrete relief at Leonhardstrasse 13 represents not only its actual purpose but also a contribution to art in architecture.
Fawad Kazi, Concrete relief Leonhardstrasse, ETH Zurich - Building LEE, ed. Christoph Wieser, Verlag park books, 2015
