ArcelorMittal Steel Centre in Flémalle: an example for sustainable construction with steel

With its continuous commitment to sustainable development, ArcelorMittal wanted to set an example by creating a green office building: the company's Steel Centre in Flemalle (Liège) uses existing steel systems and solutions  to reduce consumption of natural resources and energy, in particular fossil fuels.

Detailed information

An all-steel design, this project owes much to its method of construction:

  • Small footprint, lightweight building
  • Superior light transmission and natural light
  • Prefabrication and control of costs
  • User comfort, energy management


Furthermore, the building was awarded “Valideo Sustainable Construction” certification in Belgium that recognises "the quality of buildings and environmental protection”.  The assessment is based on criteria such as energy efficiency, materials selection, water management, site management, acoustic comfort, visual comfort, accessibility, etc., all topics addressed in the design and construction of the Steel Centre.

An environmentally responsible operation

The planning of this office building was characterised from the outset by the aspiration to espouse an environmental strategy while adhering to strict budgetary constraints.  The specification was meticulously prepared, developed in consultation with the staff concerned in order to inform the work of the architects.

The programme and the constraints laid down resulted in architectural dispositions and special amenities such as consideration of the site in positioning the building and determining its orientation.  The choice of materials with steel as the dominant material – naturally for structure and cladding, and present even in the finishing works and furniture (700 tonnes in total) – enabled extensive prefabrication, a rapid build and dry construction.

Particular attention was paid to use and to the comfort of the personnel, in order to create a stimulating working environment and avoid costly operation.

The incorporation of energy- and resource-efficient systems and systems based on renewable energy tend to make this a "passive” building.  Ultimately, one hundred and fifty measures relating to sustainable development were implemented in the building: from the choice of materials and building architecture to selective sorting, the choice of domestic appliances and maintenance products.

An industrial landscape

The vast plot on which the Centre now stands formerly housed a tubemaking plant.  Crisscrossed by heavy infrastructure connected to the nearby river Meuse, it was honeycombed with tunnels to a depth of 10 metres.  Contaminated by oil and gas, the site underwent decontamination work by the Walloon Region.  The choice of a building on piles was initially a response to this concern, avoiding direct contact with the ground.

The building’s location, set back from the very busy road that follows the river, was chosen with the idea that other commercial buildings of the same type could be built nearby in the future.  It is designed as a landmark, visible from several points and easily identifiable.

A simple and light-weight building

The architecture of the Steel Centre reflects ArcelorMittal’s aspiration not to strain the planet’s resources.  Wrought with care, its form is an expression of its function, its construction derives from reasoned decisions relating to its organisation and the materials employed.

Standing on piles, the building is simple in form: a parallelepiped 80 metres long and 16 metres wide, housing four floors of offices and common areas.  On the ground floor, a glass box houses the single-storey reception area and the staff canteen that was incorporated into the plans during the project.  They are interposed between the piles.  The vertical circulation, deliberately off-centre in the southern facade, distinguished by its raised cap on the roof, breaks the horizontality of the facade at the same time as it provides legibility for the organisation of the building.

The building’s relatively light steel structure – it is designed for a strength of 350 kg/square metre - combines circular columns with cellular beams and composite floors.  Fluid ducts pass through the cellular beams so as to optimise the total height of the floors.  The columns are visible throughout the building providing legibility in respect of the construction method adopted.

Light-filled steel architecture

Natural light floods into the building from all directions, thereby limiting the use of artificial light, which is controlled by an automated system that obviates unnecessary consumption.

Indeed, the building is very generously glazed with curtain wall system on all four facades.  The south facade, fitted with double glazing that reduces solar radiation, is characterised by a series of broad horizontal bands made of coated steel sheet.  These bands, closed off at each end by a vertical strip, extend beyond and frame the facade.

Light transmission is addressed not only on the facade, but also in the interior fit-out and it induces patterns of use.  Placed exclusively on the facades to take maximum advantage of natural lighting, all the offices, the majority of which house two to four people, are separated from the corridors by fully-glazed partitions; the gable end offices are open-plan.  This allows natural light to penetrate to the heart of the building and in certain instances to have a dual visual orientation.

When daylight becomes insufficient, the lights automatically take over when a human presence is also detected.  The lighting fixtures are incorporated in the suspended ceilings; there is no provision for desk lamps.

Between floors 1 and 2 and between floors 3 and 4, shafts are provided to create airy volumes and break up the linearity of the storeys.  Where these shafts are located, there are double-height relaxation areas.

Acoustic and thermal comfort and use of renewable energy

Whether for heating, electricity or water management, the systems adopted are energy efficient and, wherever possible, utilise renewable energy.

Thus, in addition to their aesthetic appeal, the perforated sheet steel suspended ceilings have an acoustic and thermal function.  Coils placed in contact with the plate provide even distribution of heat or cool, depending on the season.  They are connected to a heat pump fed by seven boreholes from 15 to 30 metres deep.  Thus, while the winter was relatively cold in the first year of operation, use of the standby gas boiler proved to be unnecessary.

A mechanical ventilation system renews the air in the building between the offices, corridors and toilets, the facades having no openings except in way of the lifts.

The furniture, identical in all offices but adaptable to each individual – height adjustable desks, ergonomic chairs, etc. - is designed using non-emissive and acoustically absorbent materials.

The water for the sanitation system comes from a cistern fed by rainwater.  Solar collectors on the roof feed the hot water system and photovoltaic panels, incorporated into a canopy near the building, contribute to the electrical supply.

Fire engineering

An engineering approach was adopted in order to comply fully with the regulations.  Thus, the structural columns are filled with reinforced concrete and only the beams situated in way of the columns are protected by flocking.  Thanks to the latest studies in the field of fire engineering conducted by the R&D teams, only one beam in three had to be protected.

Besides the satisfaction of a well-defined, perfectly tailored approach, this solution provides greater design freedom and is appropriate to a tighter economy.

Fast and safe construction

The attention paid to the building’s operation to the ultimate benefit of the users and in the interest of the client is reflected in the construction operation.  Indeed, the steel structure results in extensive prefabrication and a so-called dry site with reduced environmental impact.  With an erection time for each storey of only fifteen days, the construction operation lasted a total of sixteen and a half months.  The timetable established at the outset was scrupulously observed, a sufficiently rare occurrence in construction to be worthy of mention here.

Furthermore, and in accordance with the initial objective, the construction operation took place under conditions of strict safety.

Gérald Jacques, the director of the Steel Centre followed the project from A to Z: "The construction of the Steel Centre was an opportunity to reflect and to define specific objectives in keeping with sustainable construction from the design stage.  We incorporated both the transportation of materials – the least possible - the safety and cleanliness of the construction site and energy efficiency, by targeting non-consumption of fossil fuels, end of life recycling and user comfort, disabled access.

We wanted to apply to one of our buildings the 'passive building' approach using a maximum of Group products, thereby demonstrating that steel in construction fulfils the requirements of sustainable development.  Furthermore, the building has been awarded “Valideo sustainable construction" certification and, moreover, an assessment of its performance in operation is planned."

Project Information

  • Flémalle - Liège
  • Belgium
  • Architect:
    Art & Build
  • 2008
  • Client:
    Groupimo ArcelorMittal
  • Engineering Firm:
    BCT and groupe Arcadis
  • Contractor:
    BC Projektteam, Atelier du verre and Spehar et associés
  • Photographer:
    ©Art & Build and ©Marc Detiffe
  • Text:
    Eve Jouannais