The German nursery "Hansel and Gretel" in the French city of Nantes

Once upon a time ... The nursery that saved ThermoZYKLUS from overheating

At the beginning of January 2008, the German nursery "Hansel and Gretel" opened its doors in the French metropolis of Nantes. This 400 m² associative nursery was designed with an ecological approach: Orientation of the building towards sunlight, vegetated roof, use of solar panels for heating and hot water production ... To provide optimal comfort to the children, underfloor heating was installed in all living spaces, whether for the very young who crawl on all fours through the day, or for the older ones who play on the floor ... But the installation of this underfloor heating was not easy: because of the inertia of the system, the temperature was too high, much to the detriment of the living conditions of the children and the staff. To solve the problem, the director of the nursery and its heating installer chose the autoadaptive single room control system from ThermoZYKLUS .

A design that guarantees the highest level of comfort for children in an environmentally friendly way

The bilingual German-French nursery Hansel and Gretel offers space for 30 children, cared for in the respective language by an eleven-member part-time staff team from the two countries. In this way, the children learn the two languages without any problems, even at their youngest age.

Another aspect of the associative nursery is also admirable: the will to keep its negative impact on the environment as low as possible. This allows, among other things, the kitchen, some of which are organic, the information addressed to families on the use of ecological layers, and especially the construction of the building, which complies with the standards of sustainable development.

So, in fact, the association gave an order for a comfortable and environmentally friendly 400 m² building on 1000 m² of land. The goal was to create optimal living conditions, as well as uncompromising respect for bioclimatic standards:


  • Orientation of the building and windows according to solar radiation in order to take advantage of it and thus reduce electricity consumption.
  • Creating roof overhangs that provide shade in the summer to keep caloric intake in check
  • Use of recyclable materials, while ensuring acoustic and physical comfort (e.g., soft floor to protect children from injury in case of falls)
  • Creation of a vegetated roof
  • Humidity control for better hygrothermal comfort
  • ...
Under these conditions, the heating system underwent a thorough study. The areas for staff and parents (reception area, staff rooms, changing rooms, offices) were equipped with radiators. On the other hand, in the children's areas (activity rooms, dining room, corridors, kitchen, bedrooms), underfloor heating was installed to provide comfortable temperatures for the children playing or crawling on the floor.

Heating and hot water production is provided by PHOENIX SOLAIRE, through its 21m² PHOENIX solar collectors, and the support of a DE DIETRICH gas condensing boiler in case of insufficient sunlight.

The inertia of the floor heating causes the overheating of the building

In the first months, users quickly realize that the floor heated areas are impossible to regulate due to the inertia of this material. The temperature is constant at 26 to 27 °C, and for the "big ones" (18 months - 3 years) in the south-facing areas, the situation is even worse ... thermal comfort is poor and energy is wasted because the windows are open non-stop. Mrs. RABIN, director of the nursery, needs to find a solution as soon as possible to bring the temperature back to a normal base of 19 to 20 °C. So she decides to use the autoadaptive single room control system from ThermoZYKLUS.

ThermoZYKLUS, the solution to optimally regulate the temperature in the different habitats.

So, two months after its opening, the nursery is buried in the children's areas with the THERMOZYKLUS system. The installation is completed in only 3 hours: a quick application. Only the following elements need to be added to the existing system:


  • Solenoid valves on heating circuit manifolds in the equipment room
  • A control center to process the information received and anticipate the temperature evolution in the different rooms. Deployed in the director's office, the control center monitors and controls temperatures in real time.
  • Room thermostats that measure the temperature in each room and transmit the data to the control panel via a single receiver.

For Mrs. RABIN, "the effect is radical. The temperature is now controlled, and it is very pleasant to be able to regulate it individually in each room. We can, on the one hand, heat the bedrooms a little so that the children have a comfortable sleep, and on the other hand, heat the activity rooms to 21 °C when we do water games. In short, we really feel like we're providing a more comfortable and healthier atmosphere for the kids!"

A new project for even more energy savings and ideal thermal comfort

The ThermoZYKLUS system causes energy savings by avoiding overheating of the building, but also by the possibility of programming lowering temperatures. For example, since the nursery is empty on weekends, the temperature is lowered on Friday evenings and raised again on Sunday evenings. This way, the building is not heated unnecessarily, but when the children arrive on Mondays, the temperature is comfortable again.

Everyone involved is so delighted with the result that the rooms heated by radiators will soon also be equipped with the heating control system from ThermoZYKLUS ; another step for the nursery on its path to environmental conservation.

Press contact : Marie-Christine Joubert