Night-time cooling and natural ventilation for Swiss school

In order to make the Lindenbüel school building in Volketswil fit for the future, the windows of the school building were retrofitted with electric window drives as part of an extensive renovation. Thanks to automated natural ventilation and night-time cooling, the indoor climate has improved noticeably, and the investment has also paid off in terms of energy efficiency.

Sustainable school: improved indoor climate and reduced energy consumption

The Lindenbüel school building in Volketswil, Switzerland, needed renovations to be more resource-efficient, sustainable and comfortable in the future. One key objective was to use natural ventilation and night-time cooling to improve the indoor climate while promoting sustainable and resource-efficient building operation. The goal was to make the building fit for the future in the face of climate change. To this end, the windows needed to be equipped with electric drives and a control system needed to be installed on site.

Sustainable school renovation: Why an energy-efficient façade is essential

View of a tilted roof window from below

Fanlight in the school corridor for ventilation and as a source of light. © Lorenz Frey / GEZE GmbH

For economic and environmental reasons, buildings are being used for longer and longer periods of time. Legal requirements such as the Climate Protection Act and the European Green Deal are reinforcing this trend, as they drive renovation projects and set clear requirements for building energy efficiency. As a result, energy efficiency in existing buildings must be significantly improved.

Automated façades in particular can deliver impressive improvements in energy efficiency, comfort and safety. This does not always require the entire façade to be replaced. Often, simply retrofitting manual windows with electric window drive can significantly improve a building's energy balance.

Retrofitting smart window drives can be carried out quickly and cost-effectively as part of a building renovation . Networked via the IQ box KNX, windows can be integrated directly into the building automation system and conveniently controlled via the building management system. There are many reasons to use this kind of retrofitting and automation, particularly in schools.

6 good reasons for natural ventilation with electric window drives via building automation

In view of changing climatic conditions, schools must find ways to make their buildings usable and comfortable in order to ensure stress-free learning and teaching. One relatively straightforward solution is to use natural ventilation in the form of an energy-efficient façade. Building automation allows classrooms and common rooms to be air-conditioned more comfortably for pupils and staff – without the use of costly and energy-intensive air conditioning units.

Smart building automation: advantages of control via KNX

View of an electrical installation cabinet

Corridor IQ box KNX HS controllers integrated into the customer's electrical installation cabinet. © Lorenz Frey / GEZE GmbH

When controlled via a KNX module, the window drive responds to commands such as "open" or "close". The KNX system, which is not installed in the drive itself, but on site – this is in a control cabinet in the Lindenbüel Volketswil school building, – is what makes the system intelligent.

Controlling the window drives via an intelligent KNX module offers a wide range of intelligent and flexible control options that can be used as needed.

  • Sensor-based automation
  • Time and scene control
  • Central control unit
  • Integration into the building management system
  • Logical connections
  • Integration into security and fire protection systems

Learn more about the KNX module

Natural ventilation for the Lindenbüel school in Volketswil

View of the school corridor with a glass door, the upper window of which is tilted open.

The chain drive responds to commands such as open or close. © Lorenz Frey / GEZE GmbH

Classrooms with open passage doors and window fronts on the right

The successful pilot project marked the start of retrofitting all windows with the GEZE Slimchain. © Lorenz Frey / GEZE GmbH

This range of advantages – creating the best possible indoor climate for working and learning with automated natural ventilation and night cooling, while saving resources and energy costs – was why the school chose the system.

GEZE Switzerland Ltd. was chosen as the partner for the planning, products and implementation of the project: with the GEZE Slimchain chain drive, GEZE offered an ideal product for the requirements of this project. In combination with the IQ BOX KNX, they are connected to the KNX module and thus integrate seamlessly into the on-site control system. Modern building automation can be used to achieve optimal ventilation. Centrally controlled, the drives open and close the fanlights in the classrooms and corridor, contributing to a pleasant indoor climate.

Convincing measurement results: from sample windows to comprehensive retrofitting

As a first step, the client initially wanted to convert a single room. After extensive consultation, a sample window was equipped with the GEZE Slimchain chain drive and the IQ Windowdrive. Data was collected and compared over the course of one summer. Outstanding data from the pilot project then provided the basis for conversion of the entire school building. In the further course of the project, a total of 121 drives, as well as associated electrical components, were installed. This extensive work was carried out in two stages: first, some of the classrooms, doors and corridor windows were converted and put into operation. Additional classrooms were added in a further stage. Both installation and commissioning were carried out by GEZE Switzerland. To ensure trouble-free operation, thorough instructions were given to the technical service on site.

The customer is delighted with the smooth implementation of the project and the high-quality product:
 

Working with GEZE Switzerland AG, our customers enjoyed a comprehensive, worry-free package – from expert advice and sample windows, which delivered convincing measurement results over an entire summer, to professional installation and handover.

Nathan Grob, Commercial Technical Advisor at GEZE Switzerland

Renovation during ongoing operations: Possible thanks to optimal project planning

Completing renovations while operations are ongoing should be considered not only in schools, but whenever a building can only be vacated for renovation at great expense. At the Swiss school, this was possible with some restrictions, and the main objective – to keep the school running – was achieved. To this end, one part of the building was cleared during each construction phase, while lessons continued in the other part. This meant that the extensive work was not limited to the short time frame of the summer holidays, but could also continue during normal school hours.