New Velux modular canopies from Tomi Ungerer college in Dettwiller for a successful energy renovation

Affected by a problem of early obsolescence, the college of Dettwiller was looking for 5 years a viable technical and financial solution to renovate its original roof windows, an investment up to € 300. The solution provided by VELUX modular canopies made it possible to renovate the whole in record time, while guaranteeing an exemplary level of thermal comfort.

While a draft decree will be published as part of the Energy Transition Law, obliging tertiary buildings of more than 2000 m2 to improve their energy performance by 25% by January 1, 2020, VELUX France is once again putting its know-how in the field of sustainable building at the service of energy renovation.

A modern but prematurely degraded building

Built in the 90s, the Dettwiller secondary school now welcomes 252 students divided into 11 classes over a total area of ​​3850 m2. Equipped with three dilapidated canopies, several of which were cracked, the building exhibited high heat losses for its occupants. "It became urgent to replace the entire structure and have good insulation of the building while retaining the beneficial contribution of natural light", specifies Thierry Cabiener, County Councilor of Bas-Rhin (Canton of Saverne).

For Claude Meyer, Principal of the Tomi Ungerer college: “As head teacher, my primary mission is to provide the best possible working conditions for the students. With the old installation, we had sealing problems which forced us to sometimes delimit security perimeters, but also temperature problems, since it was too cold in winter and up to 35 ° C in summer , preventing from running upstairs ".

The company Wiedemann & Fils won the call for tenders to manage the renovation of the college's three canopies thanks to a solution which proposed installing VELUX modular canopies. The renovation of the glass roofs took place during the summer school holidays so as not to disturb school life.

A technical challenge for improving thermal comfort in summer and winter

The college had three original canopies with manual ventilation and smoke extraction which had not worked for several years. The main challenge of this project was therefore to replace this obsolete structure while providing natural ventilation in the establishment, and this taking into account a technical constraint on the main canopy: a drop between the start and the end of the canopy (1,7 m apart).

This project met a double objective:

• For VELUX: demonstrate, through its innovative solution of automatic opening modular canopies, the benefits in terms of thermal comfort, natural light and reduction of the establishment's heating budget;
• For middle school: provide students and teaching staff with better school living conditions through better ventilation and more abundant natural light, and this in anticipation of the upcoming decree under the Energy Transition Law.

The new modular VELUX canopies now guarantee thermal comfort in summer and winter in the building.

In winter, the thermal study of the building thus indicates an overall decrease of 5% in the total heating consumption of the college, and up to 38% for the premises adjoining the glass roofs (Circulation, Circulation-Reception, CDI) *.

In summer, the double glazing with solar control of the new canopy, combined with its automatic opening, allows, by natural cooling, to lower the indoor temperature by almost 9 ° C (compared to the old canopy).

“With this renovation and the replacement of the windows, we will make significant savings, which will benefit students through school life. In addition, the rendering is very aesthetic: this is an important point because it is also a factor of attractiveness so that the parents of pupils choose to enroll their children in our establishment ", adds Claude Meyer, Principal of Tomi Ungerer College.

“After having set up a monitoring program for indoor air quality at a nursery school in La Manche last spring, we are delighted to be able to contribute again, thanks to our innovations, to improving thermal comfort and the energy performance of buildings ”, concludes Catherine Juillard, Director of Sustainable Buildings and Institutional Relations at VELUX France.

* According to Tribu Energie thermal study, Impact of the replacement of the glass roof and its automation - November 2016

** According to Tribu Energie simulation study - average drop of 8,8 ° C in the “Traffic-Reception” area, between 8h and 17h on a typical day in June.