Passive Witness House CLK

Last modified by the author on 30/01/2019 - 09:56
  • Building Type : Isolated or semi-detached house
  • Construction Year : 2016
  • Delivery year : 2017
  • Address 1 - street : 8818 GREVELS, Luxembourg
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 179 m2
  • Construction/refurbishment cost : 525 000 €
  • Number of Dwelling : 1 Dwelling
  • Cost/m2 : 2932.96 €/m2

Proposed by :

Certifications :

  • Primary energy need
    27.8 kWhep/
    (Calculation method : RGD du 30 novembre 2007 - bâtiment d'habitation )
Energy consumption
Economical buildingBuilding
< 50A
51 à 90B
91 à 150C
151 à 230D
231 à 330E
331 à 450F
> 450G
Energy-intensive building

Being heavily involved in passive constructions, we wanted to create a thoughtful and sustainable building. We equipped our control house with a complete EnOcean wireless home automation system. This innovative technology works without any battery or wiring. The energy recovered during the manipulation is enough to emit a radio signal, which makes it possible, for example, to turn on the light. Products and systems with EnOcean technology are perfectly integrated into the usual home automation systems, regardless of whether these systems communicate via LON, KNX, BACnet, TCP / IP or Ethernet. This allows the implementation without much work of the concepts of sustainable energy management.

Data reliability

3rd part certified


Construction Manager



    Bureau d'Architecture Urbaine SARL

    Radu Axinte

    Realization of architectural plans


    Claude Goetz et Carlo Posing

    Implementation of the home automation system

Owner approach of sustainability

The goal was to build an avant-garde house that reflects the philosophy of the company: our wish was to have an energy-efficient house, with efficient materials, photovoltaic panels, solar thermal panels, a powerful heat pump , all with an extremely well insulated energy envelope and a perfect airtightness (N50 = 0,26h-1). We also wanted this house to be sustainable, which is why we used EPFC certified materials and a rainwater recovery system.

Architectural description

We wanted a very modern architecture by highlighting the assets of the house which has an exceptional view to the back. All living rooms have been oriented so you can enjoy this view. We have created the space in such a way that the intimacy of the occupants is respected while keeping passive requirements in mind. The house consists of large open spaces, beautiful ceiling heights, a skylight in the kitchen and large windows.

Energy consumption

  • 27,80 kWhep/
  • 45,00 kWhep/
  • RGD du 30 novembre 2007 - bâtiment d'habitation

  • 35,00 kWhef/
  • Heating installation: 1071 kWh
    Domestic hot water preparation: 681 kWh

Envelope performance

    Insulating facade value U 0.12 W / m2K
    Slab against earth value U 0.08 W / m2K
    Ceiling attic height U 0.07 W / m2K
    Chassis: Ug 0.5 W / m2K; Uf 1,1 W / m2K

    EN 13829 - n50 » (en 1/h-1)

  • 0,26
  • We chose this type of installation to match our ecological fiber and to limit electromagnetic waves as much as possible. By this system, we have much less electrical wiring, no batteries and radio waves propagate only during the fraction of a second during which we press the push button.

    We can at any time on our Gsm by a very intuitive application to control the shutters, turn on the lights. We use it mainly to simulate our presence when we are traveling and returning later than expected. But we also use it for ease when we are in the couch.

    Being able to check at all times that the windows and doors are closed is very reassuring as well.

    The weather station also protects our house from overheating and lowers the blinds from the indoor temperature we choose. With indoor temperature and humidity probes and outdoor temperature and temperature sensors, we can regulate and control everything.

    Now that we have got used to it, it would be difficult for us to do without it.


    • Heat pump
    • Low temperature floor heating
    • Solar thermal
    • Heat pump
    • Solar Thermal
    • Others
    • Double flow heat exchanger
    • Solar photovoltaic
    • Solar Thermal
    • Heat pump
  • 100,00 %

Smart Building

    Transverse energy optimization: automatic shutter closure
    Recovery of free energies: recovery of rainwater
    Home automation system: EnOcean, with a clean energy consumption of almost zero
    Easy management of the temperature of the parts, control of the closing of the chassis, understanding and warning in case of water leakage.
    Smart Grids planned to work with self-produced electrical energy storage systems
    -relative energy
    -power supply
    -energy production

    Home automation allows the monitoring of the production and consumption of the whole installation: photovoltaic panels, technical, ventilation, production, rest of the house for electricity, as well as consumption of rainwater and city water . Possibility of making data available in the cloud.

GHG emissions

  • 5,60 KgCO2/m2/an
  • CPE Energy Performance Certificate

Life Cycle Analysis

    Lifecycle and durability analyzes as well as deconstructability analyzes were calculated according to the Luxemburg Lenoz reference system.

Water management

    No sufficient return on the building at the moment as it is our Witness House.
    10 000 l cistern in operation.


    Motiv340 swing door



    Second œuvre / Menuiseries intérieures, serrurerie, quincaillerie 

    White lacquered wood door, honeycomb core with slightly rounded door frame and linear hollow pattern

    It was important for us to work with quality materials, which is why we chose these eco-certified doors.

    Oak Rome




    Second œuvre / Menuiseries intérieures, serrurerie, quincaillerie 

    oak engineered hardwood floor "eiche rom" rustic look

    It was important for us to work with quality materials, which is why we chose this eco-certified parquet.

    Sylitol® organic interior paint



    Second œuvre / Peinture, revêtements muraux

    High quality interior silicate paint, solvent free. Suitable for use in spaces used by allergic patients.

    The interior painting is one of the elements with which the occupant is in direct contact and the non-harmful character is very important in this respect.



    [email protected]

    Second œuvre / Equipements électriques (courants forts/faibles)

    The combination of miniature energy harvesting modules and ultra-low power radio technology makes it possible to offer innovative sensors that require no maintenance. These self-powered switches and sensors therefore operate wirelessly and offer unparalleled flexibility of use as well as increased time and energy efficiency. All while limiting investment and operating costs. Wireless, self-powered sensors and switches using the EnOcean wireless standard are an ideal solution for sustainable building applications. This power supply by movement, light or temperature makes cables and batteries for switches unnecessary, as well as for collecting information from sensors such as: Temperature, water or presence sensors. The sensors and actuators can communicate directly with each other and / or can be controlled by a controller / gateway placed in the room via a cloud interface for applications requiring remote management and control via a computer or smartphone.

    Vitocal 242-S compact heat pump unit


    Christian Haus - [email protected]

    Génie climatique, électricité / Chauffage, eau chaude

    Split version System combination with Vitovent 300-F home ventilation system with central control unit for heating, hot water, solar system and ventilation

    Solar flat plate Vitosol 200-FM


    Christian Haus - [email protected]

    Génie climatique, électricité / Chauffage, eau chaude

    for DHW heating, with overheating protection ThermProtect

Construction and exploitation costs

  • 46 764,80
  • 20 468

Urban environment

Our house is located in Grevels, part of the municipality of Wahl in the canton of Redange.

Land plot area

934,00 m2

Built-up area

18,00 %

Parking spaces

A garage (2 cars) + outside parking

Building Environmental Quality

  • indoor air quality and health
  • water management
  • energy efficiency
  • renewable energies
  • products and materials

Reasons for participating in the competition(s)

EnOcean technology enables a smart connected home. This intelligence is invisible, it warns and also allows to control the data, this by spending no energy and emanating less waves. This technology requires less raw materials (no batteries, less cables) and allows a great modularity, that is to say that the house evolves according to the needs of its inhabitants. Finally, the smart home allows great energy savings thanks to the management of overheating and automatic shutter closing or the management of room temperatures and control of the closure of the chassis. On the other hand, the smart home also allows for a better understanding of lifestyle habits via data.


Here are the features that have been integrated into the sample house:

- energy saving

- temperature control

- Control of consumptions / productions

- Smart shading

- Consistent lowering of blinds

- Systematically turn off the lights

- security

- turn off everything

- Control of window openings and doors

- Simulation of presence

- Alarm

- Comfort

- Central visualization and control of the entire electrical installation

- Timed lighting control

- Automatic shading

- scene control

- Programmable positions for blinds and shutters

- Surgery

- PC with / without Touchscreen

- Tablet Apps

- Smartphone Apps

- Remote control

- Voice command

Building candidate in the category

Smart Building

Smart Building

Coup de Cœur des Internautes

Coup de Cœur des Internautes

Green Solutions Awards 2018 - Bâtiments

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Laura Varisano

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Green Solutions Awards 2018 - Bâtiments