Steps away from Paris’ bustling business district and the Grand Arche de La Défense, the InDéfense & Hôtel OKKO project combines office and hotel program in a single unique, faceted structure.
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3XN is proud to share its first completed project in France, a 16,000 sq m office building and hotel in Nanterre, France. Developed by VINCI Immobilier and realized in collaboration with Paris-based SRA Architectes, the two-building project anchors the growing Les Groues district in Nanterre and boasts views onto La Défense and the Grande Arche. À quelques pas de l’effervescence du principal quartier d’affaires de Paris et de la Grande Arche de La Défense, le projet InDéfense & Hôtel OKKO associe un programme de bureaux et un hôtel dans une structure unique aux multiples facettes.
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“As the first shape you encounter when arriving from La Défense, this building had to be eye-catching and dynamic”, says 3XN Founding Partner Kim Herforth Nielsen.
“The faceted façade and shifting volumes make it a standout in the busy district. The concept – two distinct but complementary designs – is unique in the area.”
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In a single 16,000 sq m structure, the building combines a mixed program open to the city. Within the office building and hotel, collaborative spaces and a wide range of food options are available to users, while food venues open to the public participate in the animation of the street and the neighborhood on the ground floor.
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The project’s two programmatic elements, a hotel and an office building, are separated but adjoined along their east-west axis. Where Hôtel OKKO, clad in semi-
reflective aluminum panels, remains an unbroken mass, the InDéfense office building is split and shifted into smaller masses, each pushed in or extruded to
open the long and narrow site to its surroundings and add depth to the façade.
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A sheltered agora, used as a bike parking at the ground level, links the two buildings and is punctuated by a spiral stair. A mural, visible from the street, will be installed on the side wall of that space aiming to encourage curiosity and bring art to the city.
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Distinctive Façades
Together, the façade’s angled and tinted aluminum cassettes give it a nearly lenticular quality, appearing glassily transparent or colorfully metallic depending on the viewer’s perspective, the time of day, and even the season. Within the context, the reflective façade of the Hôtel OKKO stands out of the context and gives the program its own identity, while the distinctive bronze-tinted façade of the InDéfense building brings warmth and atmosphere in the neighborhood.
InDéfense
The visual transparency of the open atrium spaces allows for easy visual access across the building, facilitating knowledge sharing and encouraging social interaction across floors and departments. Visible from the exterior on the north facade, the spiral staircase that links the floors echoes its exterior twin and highlights the complementary architectural nature of the project.
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Stairs connect more than floors
The building is organized around an interior spiral staircase set within an atrium
adjacent to the full-glazed north façade. Those stairs are designed to encourage
interaction, communication and knowledge sharing among the colleagues sat across the building’s floors. The staircase, which alights on each level adjacent to elevator lobby, requires passing through the floor’s shared landing – facilitating opportunities for interaction between colleagues separated across the floors.
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The façades of the office building are designed with openings for ventilation cuts
integrated within the opaque cassettes (through a perforated side-panel) to offer
a “clean” design made of solid panels and large glass panels with no visible frames.
The checkerboard composition of the façade contributes to thermal regulation and creates a light and shadow effect in the work spaces, enhanced by the « californian » blinds, which allow users to adjust the occultation and are reminiscent of the facades’ architectural style. Between the boulevard de La Défense and
the railway, the structure and the façades of the buildings are designed with a high level of performance in terms of vibrations and acoustic performance.
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“On such a long, visible site, the façade had to combine beauty and functionality”, explains Kim Nielsen. “The façade’s checkerboard pattern is dynamic and aesthetic while also moderating the amount of direct light inside the workspaces.”
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The façade of the InDéfense building is a dynamic play of push and pull, the extruded/receding volumes creating shaded overhangs or generous daylit terraces. These planted outdoor spaces, in addition to providing spatial variety, incorporate both contextual and perceptual biophilic attributes – attributes proven to have positive effects on workplace productivity and wellness. The terraces distributed over different levels, the interior stairwell and its galleries as well as the two exterior staircases make InDéfense a lively building, opening up to the city, which allows everyone to see the effervescence created by its users.
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Located on the western portion of the site, Hôtel OKKO houses 184 rooms over nine
floors. On the ground floor, a restaurant is accessible to hotel customers, the
neighborhood, and to employees from the surrounding offices to create an active and busy streetscape. The first floor is occupied with shared amenities, among other things a 300 sq m lounge and a dedicated terrace for hotel visitors that they can use anytime during their stay. The interior of the hotel was designed by Studio Catoir.
This project is one of the first completed projects of a range of new developments
planned for the growing La Défense/Les Groues district and will be linked to the Greater Paris region by the opening of the new station Les Groues on the new circular M15 line and the west extension of the RER E Line. The InDéfense project is in the process of being certified HQE Exceptionnel, BREEAM Excellent, Effinergie+. Hôtel OKKO will receive the BREEAM Very Good certification.
The project was designed by 3XN, executed by Paris-based SRA Architectes and
developed by VINCI Immobilier, who is also the building’s tenant.
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