From convent to classroom: Healthy indoor air in St. Clara nursing school
High above Trier, on the Petrisberg, the former St. Clara convent has been given a new lease of life. The historic ensemble has been transformed into a modern training centre for nursing professions, now home to the Karl Borromäus School. Where nuns once lived and worked, up to around 225 students are now being trained as nursing professionals in various specialisations. The conversion has created a largely barrier-free learning environment that combines the calm atmosphere of the former convent with contemporary educational needs and modern building technology.
Visit a reference projectPreserving character, improving comfort
One of the main ambitions of the client and planning team was to retain the architectural character of the 1930s building while equipping it for intensive daily use as a school. Key elements of the original layout with corridors and classrooms were preserved, with only a few non-load-bearing walls removed to create larger seminar and event rooms. The distinctive, curved window forms were carefully refurbished and integrated into the new façade concept. These windows are now a defining architectural feature – and at the same time an important source of generous daylight that supports a bright, welcoming learning atmosphere. The valley-facing façade is part of a protected ensemble, so its silhouette remains almost unchanged, keeping the history of the site clearly visible.
A natural ventilation concept for healthy learning environments
As part of the technical refurbishment, the project team looked for a ventilation strategy that would respect the historic building fabric, support energy-efficient operation and ensure a healthy indoor climate. Instead of installing large mechanical ventilation units with extensive ductwork, the planners opted for natural ventilation via automated windows, using WindowMaster’s Embedded® system. The WindowMaster solution is implemented in three event and seminar rooms – two on the first floor and one on the second floor. Each room forms its own NV Embedded® zone with independent control. The concept uses cross ventilation between the north and south façades: • pressure and temperature differences drive the natural flow of air • stale indoor air is removed without mechanical fans • fresh outside air is supplied in a draught-free way This creates a demand-controlled supply of fresh air with a high level of comfort – and significantly lower energy consumption compared to conventional mechanical systems.
NV Embedded®: decentralised, sensor-based control
At the heart of the system is a decentralised NV Embedded® system based on WCC 320 P controllers. Each of the three zones operates autonomously and continuously monitors the relevant room and weather parameters.
The system uses, among others:
- a room sensor (e.g. WWS 100) to measure temperature and CO₂ concentration
- wind and rain sensors, which provide weather data and protect the building
- an outdoor temperature sensor to assess thermal conditions
Based on this data, the controllers automatically open or close the motorised windows to maintain defined setpoints for air quality and room temperature.
For teachers and students, this means:
- consistently good air quality in teaching and event rooms
- fewer CO₂-related symptoms such as fatigue and loss of concentration
- a room that “thinks for itself”, without anyone having to worry about when to open or close windows
Because the NV Embedded® system works without connection to a central BMS, it is particularly suitable for projects where historic structures limit space for technical installations – while still ensuring reliable and precise operation.
Natural ventilation without visible technology
The historic character of the convent played a key role in all design decisions. The building services should support the new use as a school but remain as inconspicuous as possible in day-to-day operation. Here, the decentralised window actuators from WindowMaster offered a convincing solution: • they enable natural ventilation without large air handling units or ducts • the compact actuators are integrated into the window construction and remain visually discreet • ceilings and walls in the rooms stay largely free of technical installations, which benefits both acoustics and interior design In this way, the project achieves a careful balance: the building remains recognisably a convent in its appearance, while the interior is equipped with modern functionality for a contemporary nursing school.
More comfort, less energy – for people and the environment
With the selected ventilation concept, the project pursues several objectives at once:
- Healthy indoor climate: Continuous monitoring of temperature and CO₂ ensures that air quality meets the expectations for a modern educational building.
- Energy efficiency: By making targeted use of natural driving forces for ventilation, the system helps reduce the energy needed for conditioning the rooms.
- Operational reliability: The window actuators and controllers work robustly and precisely – an important factor in the daily routine of a busy school.
The overall energy concept is supported by a modern heat pump system, which further reduces CO₂ emissions and improves the energy performance of the building.
Taken together, Kloster St. Clara demonstrates how heritage architecture, energy-efficient operation and modern comfort can be successfully combined in a single educational facility.
A learning environment with a future
With the move of the Karl Borromäus School into the former St. Clara convent, a training centre has been created on the Petrisberg that convincingly brings together tradition and modern teaching. The historic architecture remains tangible, while intelligent building technology quietly works in the background to provide a healthy indoor climate. The intelligent indoor climate solution helps the school offer its students a future-oriented learning environment – with fresh air, good concentration and room conditions that support the demanding training in nursing professions.
“St. Clara shows how natural ventilation can be integrated into a historic building without compromising its character. Our NV Embedded® solution provides healthy, energy-efficient fresh air in the seminar rooms – to the benefit of students, operators and the environment alike.”
Peter Jung
Key Account Manager