No "blue box"

At the Westbahnhof train station in Vienna, IKEA has built a new-generation store. It is designed in an urban sustainable style, with the building surrounded by 160 trees and offering a publicly accessible rooftop terrace. Architects from querkraft Architekten created a façade for the building using aluminum window and façade systems from Schüco, which references the traditional shelving systems of the Swedish furniture manufacturer with its gridded structure.

IKEA aimed to present itself as a "good neighbor," which for the new building project of nearly 30,000 m² near Wien Westbahnhof meant moving away from the typical "blue boxes" associated with its stores. For the new retail district being developed close to the former main Vienna train station, it was necessary to design something distinctive – an open, urban building that offers quality architecture and relies less on bold colors and large logos.

"It was an unusual collaboration with a bold client," summarizes Jakob Dunkl, one of the three owners of querkraft Architekten. "The city of Vienna had several challenging requirements. The building was to be completely car-free – no parking spaces for employees were allowed – and a publicly accessible terrace was to be on the roof. Not only did IKEA meet all these requirements, but its representatives were also very open regarding suggestions for other aspects, such as corporate identity. Therefore, there is much less blue and yellow on the building, and the company's logos are significantly smaller."

A three-dimensional urban park with 160 trees

The architects designed a project reminiscent of IKEA's product range, a seven-story steel structure inspired by traditional shelving: the outer façade alternates between glass-encased closed cubes and open sections with a steel frame featuring greenery in planters. Sonja Mitsch, project manager at querkraft Architekten, comments on the concept: "To create enough space for the new building, a 19th-century building was demolished. If you asked residents what should replace that building, the most common answer would likely be a park. Therefore, we created a three-dimensional park within the new urban IKEA store, featuring more trees than would be found in an equally sized area of greenery at ground level."

In total, there are 160 trees growing in the building and its surroundings, placed in white steel planters up to 190 cm tall. Each of these planters is equipped with an automatic, sensor-controlled irrigation system that can respond to the individual watering needs of each plant.

When selecting the individual plants, the landscape architects chose species that thrive in Vienna's climate or those commonly found in southern Sweden, which is IKEA's home. Thanks to the green concept, the first urban store of IKEA is one of the first buildings to achieve platinum level certification from GREENPASS. This system evaluates buildings and neighborhoods based on six urban and three bonus criteria, including water, climate, air, biodiversity, energy, and costs. The new building also received an outstanding rating in terms of BREEAM certification (rating "Excellent"). The impact of plants on the urban climate can also be measured quantitatively. Based on simulations carried out by the project team, greenery reduces the air temperature around the building on a typical warm day by up to 1.5 °C at sidewalk level. From a perceived temperature perspective, the effect is even greater.

Several stories under one roof

Part of the sustainable concept is that IKEA shares the building with other users. The fifth and sixth floors are occupied by the Jo&Joe hostel with 345 beds. On the ground floor, a smaller section on the southern side is dedicated to independent shops, most of which operated in the original 19th-century building. This new construction connects with a series of shops on Mariahilfer Straße, creating a significant endpoint towards the Wien Westbahnhof station and the urban road Wiener Gürtel.

However, the architects created the biggest public attraction directly on the roof of the building. An impressive skeleton of white-painted steel rises as an open pergola, highlighted by solar panels and slatted shading. It conceals a public terrace that stretches over the entire roof area. From here, visitors can observe the entire center of Vienna and the hills that surround the Austrian metropolis.

Reliable and flexible Schüco mullion-transom facade

Visitors can access the rooftop terrace not only from the atrium but also via an external staircase or several elevators. These elements, along with escape staircases and service shafts, were integrated into the external steel skeleton. This allows for an interior space of 50 × 60 meters to be freed up, as no stair cores or reinforcements were used in the building. "It's a similar principle to the Centre Pompidou in Paris – a building that we greatly admire," says Jakob Dunkl.

For the building's outer façade behind the steel "shelves," a mullion-transom system Schüco FWS 50.SI was chosen, which received a silver sustainability plaque "Cradle to Cradle." Glazed areas alternate with closed façade panels, which are clad with white-painted steel sheets on the exterior and gypsum board panels on the interior.

"All parts of the building's façade utilize Schüco systems. We chose these systems because we are confident that we can install dimensions that we truly want," says Sonja Mitsch.

Glazed display windows for the IKEA store

The glazed units in the bay windows are particularly large and extend from the building into the steel construction. The transparent fronts serve as display windows for the IKEA store. Each of these elements is 8 meters wide and 3 meters high, consisting of just three glass panels. The profiles of the Schüco FWS 50 system are only 50 millimeters wide, making them almost invisible between the individual elements.

On the upper floors, where the hostel is located, the glazed areas are divided into smaller sections. There are differences compared to the mullion-transom façade installed further inward. In the floors occupied by IKEA, access to the balconies is exclusively provided through balcony doors from the Schüco AWS 75.SI+ system, which are integrated as a recessed element into the mullion-transom façade. In the hostel, there are many manually operated windows from the same Schüco system. However, these windows have a locking mechanism preventing them from opening fully, allowing only for tilting. This is primarily for safety reasons, as not all balconies can be accessed – most do not have any railings and are only used for potted plants.

Four storeys of the store with a central atrium

The sense of openness that radiates from the building into the surrounding world continues inside. The lower four floors are used by IKEA – housing the main store, the self-service area, and the obligatory restaurant. Escalators surround the central atrium, rising to the fourth floor. Access to the hostel and the rooftop terrace can additionally be achieved through traditional staircases or elevators.

Inside the building, a 4.5-meter-deep steel structure is replaced by a reinforced concrete skeleton with approximately ten-meter spans. The large distances between the supports allow for flexible use of the spaces and frequent changes in terms of furnishings. The interior is dominated by exposed concrete ceilings with visible piping, smooth-finished concrete floors, screeds without any additional coverings, white-painted steel, and plenty of glass.

The spaciousness of the interior is also supported by the fire protection concept. The entrance areas, atrium, and the second and third floors form a joint fire section. In the event of a fire, the first floor can be separated from the extensive vertical spaces using fire curtains.

Safety and transparency simultaneously

In the hostel, the architects utilized effective fire protection combined with maximum transparency. The steel mullion-transom façade Jansen VISS Fire TVS EI60, which extends the full height of the floor, provides fire resistance for 60 minutes around the entire atrium. Integrated into this are steel fire doors Janisol 2 EI30 and Janisol C4 EI60. One floor up, the atrium is predominantly surrounded by closed white walls. Views from the hostel into the open space are provided only by a few individual fixed elements of the fire and smoke-tight system with 60 minutes of fire resistance Schüco ADS 80 FR 60 with fire-resistant glazing.

Floor plans with a depth of approximately 50 meters are advantageous for a furniture store, but this layout posed a significant challenge for the hostel operations. To ensure that the interior spaces were sufficiently lit, the architects added two new two-story courtyards and a three-story courtyard on the fifth and sixth floors – in addition to the large atrium that spans all floors. The mullion-transom façade Schüco FWS 50.SI is also used in the courtyards – here, however, these elements also have fire protection functions in some areas, preventing the spread of potential fire through the courtyards.

The glass roof over the atrium did not require any fire resistance. However, it is extremely important for the potential smoke extraction from the building. For this purpose, the architects chose the system Schüco AOC 50 ST, which is mounted on the steel supporting structure. The system integrates two opening flues for smoke and heat extraction, which automatically open in the event of a fire.


Project Name: IKEA VIENNA WESTBAHNHOF – VIENNA CITY CENTRE
Architects: Querkraft Architekten, Vienna
Floor Area: 29,480 m²
Usable Area: 26,200 m²
Completion: August 2021