New construction Koch-Areal Zurich
June 06, 2024
Residential, commercial and park on 30,000 square meters
A completely new district with 350 affordable apartments for 900 people and commercial space will be built on the "Koch-Areal" industrial wasteland by 2026/27. The schedule is ambitious, and the large construction site demands reliability and expertise from all partners.
FROM OCCUPATION HEADLINES TO THE NEW QUARTER
The approximately 30,000 square meter site - the equivalent of more than four football pitches - takes its name from the original owner, the trading company Koch Wärme AG. The history of the site is eventful: building restrictions, but also occupation and eviction repeatedly made the headlines. In 2013, the city of Zurich bought the site and, following a concept competition, handed it over to the developers Senn Resources AG, the Allgemeine Baugenossenschaft Zürich (ABZ) and the Kraftwerk1 building and housing cooperative under building rights. Four parallel competitions were held following the approval of the "Non-profit housing on the Koch site" referendum. According to the jury, the results were a sustainable model for high-quality neighborhood development in urban density. The BZO amendment and a private design plan were further milestones on the long road to the building permit issued in spring 2023.
The development is committed to sustainability and is based on the "2000-watt site" and "Minergie-P-Eco" standards. For example, rainwater is to be used, there will be a wooden element façade, vertical greening and PV systems on roofs and façades. In addition, the public park planned by Grün Stadt Zürich is intended to characterize the district.
LARGE CONSTRUCTION SITE REQUIRES RELIABILITY
By 2026/27, affordable apartments for around 900 people as well as commercial space with a floor height of 5.7 meters and a high payload will be built. The 85-meter high-rise will catch the eye. It shows that cooperative living also works vertically. Grün Zürich is creating a neighborhood park on 12,000 square meters, in the middle of which the historic coal warehouse will remain.
The foundation stone was laid at the end of 2023 following the remediation of contaminated sites. The schedule is ambitious, and the large construction site demands reliability and expertise from all partners. Forward-looking planning is extremely important. "As a master builder, ERNE relies on the punctual delivery of plans and detailed drawings," says site manager Flavio Conti. "This is the only way to ensure optimal deployment of the construction specialists, equipment and machinery." The aim is to know three weeks in advance what will be installed and where. Suppliers and subcontractors are also informed at an early stage so that they can plan their deliveries and services.
ERNE - AN IMPORTANT PARTNER
ERNE Bauunternehmung is an important player on the large site and is responsible for the following in the construction lot of Allgemeine Baugenossenschaft Zürich (ABZ)
Master builder work for the 28-storey high-rise building
Master builder work for the adjoining row building with grocery store and large plinth terrace
The tasks include concrete work, moving the supplied staircase, parapet and façade elements and erecting the brickwork. ERNE is also responsible for the steel construction work on the underground garage ceiling, which is part of the base terrace with communal areas.
A building with 28 storeys presents challenges. All processes have to be planned precisely. Prefabricated structures support rapid construction progress, with just-in-time delivery and prompt installation. "Time is always short in our line of work," says site manager Flavio Conti. "If we can save one day on each floor, this results in a time saving of one month for a high-rise building like the one here on the Koch site."
MODERN AESTHETICS WITH LOTS OF EXPOSED CONCRETE
All ceilings in the high-rise building and all staircases are constructed in exposed concrete type 4, the most demanding category. Fair-faced concrete is a natural product and a beautiful result always depends on many factors. It depends on the sand, the cement, the aggregates and also the formwork. It must not have any holes. This is the only way to prevent "leakage". ERNE produces the formwork on site. The details of the work are planned precisely and the construction joints and formwork joints are defined in detail. The utmost care is also required during execution. In other words, the requirements are threefold: the material, the formwork and the know-how for placing the concrete.
Another challenge is moving the façade elements. The prefabricated concrete elements have to be moved between the building and the scaffolding using a crane. A great deal of dexterity is required to place them "unharmed" and precisely.
