One Nation

New Construction

  • Building Type : Other commercial buildings
  • Construction Year : 2013
  • Delivery year : 2013
  • Address 1 - street : 1, rue du Président Kennedy 78340 LES CLAYES SOUS BOIS, France
  • Climate zone : [Cfb] Marine Mild Winter, warm summer, no dry season.

  • Net Floor Area : 25 328 m2
  • Construction/refurbishment cost : 55 000 000 €
  • Cost/m2 : 2171.51 €/m2

Certifications :

  • Primary energy need :
    53 kWhep/
    (Calculation method : RT 2005 )
Energy consumption
Economical buildingBuilding
< 50A
51 à 90B
91 à 150C
151 à 230D
231 à 330E
331 à 450F
> 450G
Energy-intensive building

One Nation is a shopping center "outlet" dedicated to ETDE luxury fashion brands. It is located in Clayes-Sous-Bois, west of Paris and near the Palace of Versailles (less than 10 km).

The architect took into account the life cycle of the building in the long term. Hence the shopping center is built on a regular grid of concrete for easy modulation how businesses are distributed and to adapt over time to new shop cncepts and to the future needs of visitors.

The public areas are open to the outside and protected from the weather with a beautiful glass roof. This eliminates the air conditionning and heating consumptions in common areas.

Heating is provided by two gas condensing boilers equipped with modulating burners with oxygen regulation.

Air conditioning consumptions represents the largest energy use (before heating). It was optimized through chilled water production groups allowing free chilling for the building. The indoor air is treated with air handling units incorporating energy recovery exchangers with a thermal efficiency of 85%.

To increase the floor area ratio by 20%, the building was designed following the CERTIVEA repository "NF Commercial or Sports Buildings with HPE."

In order to achive this goal, the Energy Performance and Associated Quality level is assessed and all measures have been taken to meet this standard and make this "outlet" a Low Consumption Building.

See more details about this project

Data reliability

3rd part certified


    Thermal consultancy agency

    Bureau d'Etudes Alain Garnier

    Frédéric Ronfort

Contracting method

General Contractor

Owner approach of sustainability

The Owner wanted an exemplary building in terms of energy performance and achieve a commercial complex that is a showcase dedicated to sustainable development, while meeting the expectations of future tenants in terms of environmental quality. The objective was to show that, even in the context of a shopping center that has a bad reputation regarding its regular environmental footprint, we can make efforts to preserve the planet by choosing ingenious systems to save energy.

Architectural description

The architecture of One Nation Paris was designed by the firm of architects AWO. The architect, Gregory Genaux designed the mall around the light and natural lighting. This building has a contemporary architecture, sleek design, raw materials: the envelope of One Nation Paris "is organized around three elliptical and majestic patios, enrolled in a set of curves defining the visitor walks. These shapes of glass and concrete and free fluids create, in every corner of the building, luxurious bright and grandiose spaces, ."

Energy consumption

  • 53 kWhep/
  • 113 kWhep/
  • RT 2005

Envelope performance

  • 1 W.m-2.K-1


    • Condensing gas boiler
    • Individual electric boiler
    • Water chiller
    • Double flow heat exchanger
    • Other, specify
  • 30 %
    Heating is provided by two gas condensing boilers with modulating gas burners with oxygen control.

    The indoor air is treated with air handling units incorporating energy recovery exchanger with a thermal efficiency of 85%.

    When the outside temperature drops below 12 ° C, we produce chilled water without turning on the compressor of the water chiller groups: water is directly cooled by the outside air. The whole air-conditioning systems (networks, cassettes, winnable units, ...) have been dimensioned to operate in a 13/18°C water regime to maximize the free-chiling rather than in a 6/12°C. water regime.

    Consumption due to air conditioning which is the largest energy position (far ahead of heating consumption) has been optimized through chilled water production groups allowing operation in free cooling.

Smart Building

    A centralized technical management system is used to manage heat and cold production, monitor the energy consumption of the building and manage the lighting of the mall


    Chilled water unit with Free Cooling


    Monsieur Philippe Pineau

    HVAC, électricité / ventilation, cooling

    Outdoor unit for the production of chilled water, equipped with semi-hermetic screw compressors dedicated for the use of R134a.
    High efficiency of operation of the chiller.

    These ice water production units are equipped with FREE COOLING batteries. When the cooling load demand is continuous during the winter season or in any case when the outside temperature is less than the return liquid temperature of the installation.

    In FREE-COOLING mode the fluid is cooled by the outside air, reducing the work of compressors; can even cancel completely the work of the compressors.

    This process allows energy savings without compromising user comfort

Construction and exploitation costs

  • 900 000

Urban environment

One Nation is located in the local commercial area "Grand Plaisir". An upscale shuttles service was set up from Versailles and the Paris Opera House in Paris during the week and on weekends. Specializing in fashion and luxury brands, it includes shops dedicated to streetwear, lifestyle and sport, premium brands (Armani, Courrèges, Zadig & Voltaire, Cacharel, etc ...) and restoration with 3 restaurants and 2 chocolatiers.
Structured on 2 levels, the center and its shops offer 90 collections from the previous season prices "outlet".

Parking spaces

1,250 parking lots

Building Environmental Quality

  • indoor air quality and health
  • works (including waste management)
  • comfort (visual, olfactive, thermal)
  • energy efficiency
  • mobility

Les centres commerciaux ont, d’une manière générale, des besoins énergétiques significatifs (occupations, importance de l'éclairage artificiel, etc.). Plus particulièrement, la consommation d'énergie liée au poste climatisation est considérable (même en hiver) et voire supérieur au poste Chauffage.

Le Bureau d’études Alain Garnier a donc cherché un moyen de diminuer les consommations de ce dispositif en choisissant de mettre en place des groupes de production d'eau glacée permettant de fonctionner en free‐chilling.

Cette méthode permet ainsi de produire du froid en utilisant l’écart de température avec l’extérieur pour procéder à un refroidissement naturel, et ce sans mettre en marche les compresseurs.


Green Building Solutions Awards 2015

Author of the page

  • Other case studies



    Green Building Solutions Awards 2015