Correctional Center Bachtel, Hinwil

Client Baudirektion Kanton Zürich
Architects Clea Gross Architekten, ZürichGret Loewensberg Architekten, Zürich
Planning 2014-2018
Execution 2019-2020
Construction cost 44.5 Mio. CHF
Services Structures and excavations:
Competition
Projektierung
Tender documentation phase
Execution phase
Photos Seraina Wirz,
Baudirektion Kanton Zürich (Areal)
Engineering partner Pirmin Jung Schweiz, Rain
Awards Architekturpreis Kanton Zürich 2022 (Anerkennung)
Topics Industry/tradeInfrastructureTimber constructionConcrete constructionFair faced concrete

The project involved the conversion and expansion of the Bachtel correctional center in Hinwil. The facility is located on a terraced site in a rural setting in Zurich Oberland. Five new buildings of varying size and use were constructed while the facility remained in operation: Inmate building with 50 places, triage/visitor building, work and multi-purpose rooms, remise. The inmate- and operations-specific buildings are located in the center of the facility. The buildings for the working operations and agriculture are located near the respective production areas.
The buildings are designed as mixed structures of solid and timber building structures. The building structures of the solid construction are designed in classical skeleton structure with reinforced concrete flat slabs as well as supporting reinforced concrete wall plates and columns. The building bracing is provided by staircase cores and wall plates distributed over the building floor plans. Especially the inmate building is characterized by sophisticated fair faced concrete surfaces.
All buildings were founded using micropiles to transfer the building loads into the moraine and molasse layers. The only exception is the triage/visitor building, which was founded flat on the compact moraine.