Technical High School for Health Professionals in Ettelbruck

Last modified by the author on 07/05/2020 - 09:54

New Construction

  • Building Type : School, college, university
  • Construction Year : 2016
  • Delivery year : 2019
  • Address 1 - street : Impasse Avenue Salentiny L-9080 ETTELBRUCK, Luxembourg
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 7 237 m2
  • Construction/refurbishment cost : 10 €
  • Number of Pupil : 450 Pupil
  • Cost/m2 : 0 €/m2

Certifications :

  • Primary energy need
    39.3 kWhep/m2.an
    (Calculation method : RGD du 31 août 2010 - bâtiment fonctionnel )
Energy consumption
Economical buildingBuilding
< 50A
51 à 90B
91 à 150C
151 à 230D
231 à 330E
331 à 450F
> 450G
Energy-intensive building

Technical High School for Health Professionals in Ettelbruck won the Sustainable Construction Grand Prize of the 2019 Green Solutions Awards at the Luxembourg level + a mention for the international Sustainable Construction Grand Prize

The Lycée pour Professions de Santé in Ettelbruck, now the largest wooden building in the Grand Duchy, is a pilot project. It is indeed the first Luxembourg public building with positive energy, in other words it produces more energy than it consumes. It is also the first in Luxembourg to aim for a "Minergie-P- ECO" certification In addition to the comfort of the occupants, which reaches its highest level thanks to this certification, it is also the ecological footprint of the building that has been at the centre of attention since the design phase.

In this respect, the use of materials with a low environmental impact such as wood for the construction system, or clay panels for the interior walls, has been favoured. Also noteworthy is the use of an innovative hybrid ventilation system that combines natural and mechanical ventilation. In addition, the entire roof is covered with photovoltaic panels and combined with an inter-seasonal heat storage system, and flat solar collectors with a combined surface area of approximately 350 m2 are vertically integrated to heat the seasonal tank installed in the stairwell.

Many measures make it a sustainable building: Energy production:

  • thermal collectors on the facade with a seasonal reservoir;
  • complete roof coverage with photovoltaic panels;
  • optimization of solar gains in winter, while avoiding overheating problems in summer.

Renewable energies :

  • photovoltaic installation of 2,121 m²; 258,000 kWh/a;
  • 350 m² of thermal collectors on the facade;
  • energy storage tank (91,000 l of water, height 20m);
  • 24 kW heat pump;
  • hybrid, natural and fan coil ventilation.

Reduction of energy consumption:

  • controlled ventilation based on CO2 measurement - efficient cooling of the P.V. wave rooms by external air supply;
  • high-performance computer equipment and electrotechnical devices A++++;
  • optimized lighting (LED);
  • minimization of losses by efficient envelope (30 to 40 cm of thermal insulation).

Data reliability


Photo credit

Fabeck Architectes


Construction Manager



Owner approach of sustainability

As a pilot project for public buildings, this building reflects the state's desire to become a pioneer in technological innovation in sustainable construction, including zero energy buildings, and to guide the private sector towards sustainability and the environmental and energy performance of buildings. This is the second such experience for the State since the Nature and Forestry Administration in Diekirch is also positive energy.

Architectural description

With a gross surface area of approximately 8,400 m², the school will accommodate some 430 students in 16 classrooms and 6 clinical teaching rooms. The programme also includes an administration wing and a 200 m² multi-purpose room.

When planning the 4-storey building, several factors were predominant, including grey energy, the program and the construction system.

The decision to build a wooden construction with a system particularly adapted to this project is based on the objective of reducing grey energy. In several parts of the project, synergies were found, such as the roof covering of the sloping roof with photovoltaic panels that provide both coverage and energy production.

In addition to the criteria of sustainability, ecology and energy, which represent the pillars of the concept, other importan t elements have not been neglected, such as optimised natural lighting, acoustics, indoor climate, ecological materials, etc. This is based on the standardised energy concept for high schools, but has been adapted to the particular needs of this project.

All these factors have had an impact on the volume and layout of the project and are reflected in the architectural expression. Already the facade, with its wooden cladding and integrated solar panels, expresses the ecological character of the project. Inside the building, the water tank for energy storage is the central element around which the stairwell develops.

Energy consumption

  • 39,30 kWhep/m2.an
  • 89,80 kWhep/m2.an
  • RGD du 31 août 2010 - bâtiment fonctionnel

Envelope performance

  • 0,23 W.m-2.K-1
  • 0,21
  • 0,90


    • Heat pump
    • Solar thermal
    • Heat pump
    • Solar Thermal
    • Others
    • Natural ventilation
    • Solar photovoltaic
    • Solar Thermal
    • Heat pump
  • 275,00 %
  • The entire roof is covered with photovoltaic panels, which represents an installation of 1,550 m² and a production of 258,000 kWh/year, against an estimated requirement of 92,650 kWh/a.

    On the south-east and south-west façades, flat solar collectors with a combined surface area of approximately 350 m2 are vertically integrated.These collectors heat the seasonal tank that is installed in the stairwell. With its height of nearly 20 metres and diameter including 3.1 metres of insulation, this tank is the largest installed in Luxembourg in a functional building and offers a capacity of 91,000 litres. During the summer period, the tank is heated, the temperature can reach 95°C.

    Finally, two heat pumps with a capacity of 12 kW each complete the seasonal storage tank supply. They are installed in the exhaust of the ventilation unit and draw energy from the ventilation unit. The water injected into the heating network, with a temperature of approximately 28°C, is distributed by a floor system for the multi-purpose room, the fireplace and the cafeteria.

Smart Building

    This building has been designed to take advantage of all available resources. In addition to the renewable energy devices mentioned above, it is particularly efficient in terms of ventilation with the use of an innovative hybrid system that combines natural and mechanical ventilation. Fan coil units, with very low power consumption, allow the fresh air from the corridors to be drawn and pulsed into the other rooms. The corridor thus acts as a ventilation duct, which avoids a conventional metal cladding system.

    The building is also equipped with high-performance computer equipment and A++++ electronic devices, as well as optimized LED lighting.

GHG emissions

  • 9,60 KgCO2/m2/an
  • According to post-ADB CPE

  • 25,40 KgCO2 /m2
  • 50,00 an(s)

Life Cycle Analysis

    All the materials needed to build the school have been carefully selected to minimize their environmental impact :for example, ballasted columns instead of concrete piles, a wooden construction or clay panels for the interior walls.

    In addition to the targeted Minergie-P-Eco certification, which requires that the grey energy used to build the building be limited as much as possible, theproject also aimedto achieve a Minergie-P-Eco+ level. With this in mind, the building was designed to have a positive energy balancethat would also take intoaccount grey energy expenses.

Water management

  • 504,00 m3
  • 192,00 m3


    In addition to the criteria of sustainability, ecology and energy, which are the pillars of the concept, other important elements have been taken into account to ensure a high level of comfort for occupants, such as optimized natural lighting, acoustic performance and a temperate indoor climate.

    To contribute to this pleasant working environment in the most energy-efficient way possible, automatic and micro- perforated blinds have been installed. In summer, they allow just enough natural light to pass through to illuminate the room while rejecting most ofthe sun's rays during the day, and automatically open at nightto let the heatescape. In winter, the blinds close completely at night to keep the day's warmth. Theuse of solar energy is thus maximized, both to light the rooms and to heat them.

    Finally, it should be noted that the MINERGIE-P-ECO certification rewards the most efficient buildings in terms of home and work comfort for occupants, and guarantees above-average comfort while presenting very low energy consumption.

    De 800 à 1200 ppm

    Sans élèves < 450 ppm

    Entre 20 et 26°C


    Fan coil - ductless ventilation system

    Betic Ingénieurs-Conseils


    HVAC, électricité / ventilation, cooling

    Betic Consulting Engineers has designed a sheathless ventilation system to minimize the use of high energy grey materials. These minimalist fan coil systems, manufactured by Climalux, were installed in the building at a rate of 2 per classroom.


    Energy storage tank 91,000L



    HVAC, électricité / heating, hot water

    On the south-east and south-west façades, flat solar collectors with a combined surface area of approximately 350 m2 are vertically integrated and are used to heat a 91,000L seasonal tank. With a height of 19.89 metres and a diameter of 3.1 metres, this tank is the largest installed in Luxembourg in a functional building. It has 300mm thick glass wool insulation (0.040W/m.K) and complies with the Minergie-ECO standard.


Urban environment

The future site of the Technical High School for Health Professions is located in Ettelbruck, towards Warken, in the immediate vicinity of the other 2 high schools in the city and between the current Agricultural High School and the North Hospital.

This location on the edge of the "school campus" opens onto the main facade and its playground towards the Agricultural High School. The entrance is located on the courtyard side and access for students is from the impasse Avenue Salentiny. On the rear facade is the delivery access as well as 25 external spaces, common access with the hospital car park.

Building Environmental Quality

  • indoor air quality and health
  • comfort (visual, olfactive, thermal)
  • water management
  • energy efficiency
  • renewable energies
  • building end of life management
  • products and materials

Reasons for participating in the competition(s)

Le lycée technique pour Professions de Santé, situé à Ettelbrück, accueillera prochainement près de 430 élèves dans 16 salles de classes et 6 salles d’enseignement clinique. Le programme inclut une aile pour l’administration ainsi qu’une salle polyvalente de 200 m².

Initié par l’administration des bâtiments publics, le lycée a été conçu selon les principes définis pour les constructions à « énergie positive », c'est à dire qu'il produit plus d'énergie qu'il n'en consomme, mais accorde également une grande importance dans sa conception à l’énergie grise, à savoir l’énergie primaire non renouvelable nécessaire à sa construction et à sa démolition.

Certaines particularités marquent ce projet comme l’utilisation du bois pour le système constructif ou encore des panneaux en argile pour les cloisons intérieures. Dans l’optique de réduire au maximum l’énergie grise, le choix des matériaux s’est porté par exemple sur des colonnes ballastées pour renforcer le sol à la place de pieux en béton. Outre son intérêt purement technique, cette méthode permet de réduire l’impact environnemental du projet, comparé aux autres procédés.

A souligner également, l’utilisation d’un système hybride novateur pour la ventilation qui combine ventilation naturelle et mécanique. Par ailleurs, la totalité de la toiture est recouverte de panneaux photovoltaïques. Cette installation de 2’121 m² représente une production de 258’000 kWh/an.

Des collecteurs thermiques liés à un réservoir saisonnier ont été installés en façade. Ce bâtiment est également doté d’un équipement informatique très performant et d’appareils électroniques A+++, d’un éclairage LED optimisé. L’enveloppe du bâtiment a été particulièrement soignée avec une isolation thermique allant jusqu’à 40 cm.

Dans les façades sud-est et sud-ouest,des collecteurs solaires plats d'une surface cumulée d'environ 350 m2 sont intégrés verticalement. Ces collecteurs chauffent le réservoir saisonnier qui est installé dans la cage d'escalier.  Avec sa hauteur de près de 20 mètres et son diamètre incluant l’isolation de 3,1 mètres, ce réservoir offre une capacité de 91.000 litres. Pendant la période estivale, le réservoir est chauffé, la température pouvant atteindre 95°C. 

Ce dispositif de chauffage, le plus grand du type installé dans un bâtiment fonctionnel au Luxembourg, a été imaginé spécifiquement pour le projet et s’inscrit pleinement dans le concept global qui vise la certification très rigoureuse « Minergie-P-ECO ». Ce label, qui au-delà de prendre en compte les critères d’énergie et de confort, intègre l’utilisation de matériaux écologiques et l’interdiction de produits nuisibles à la santé.

Le Lycée Technique pour Professions de Santé est le plus grand bâtiment en bois sur le territoire du Grand-Duché, aussi bien sur base de sa surface construite que par sa hauteur.

Pour revenir plus en détail sur le système de chauffage, deux pompes à chaleur d’une capacité de 12 kW chacune complètent l’apport du ballon saisonnier. Elles sont installées dans le rejet du groupe de ventilation et puisent l'énergie de la centrale de ventilation. L'eau injectée dans le réseau de chauffage, d’une température d’environ 28°C est distribuée par un système au sol pour la salle polyvalente, le foyer et la cafétéria. Des ventilo-convecteurs, très basse consommation électrique, permettent de puiser l’air frais des couloirs et de le pulser dans les autres locaux. Le couloir fait ainsi office de gaine de ventilation, ce qui permet d’éviter un système classique de gainage métallique.

Building candidate in the category

Energy & Temperate Climates

Energy & Temperate Climates

Low Carbon

Low Carbon

Health & Comfort

Health & Comfort

Users' Choice

Users' Choice

Green Solutions Awards 2019 - Buildings

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Author of the page

Fabeck Tatiana

Architecte Gérante

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Green Solutions Awards 2019 - Buildings