On the edge of one of Santiago’s most exclusive districts in the foothills of the Andes, stands a new stadium: the Claro Arena. Designed by IDOM, the Claro Arena builds upon the former San Carlos de Apoquindo Stadium, with a retrofit and extension that triples the size of the original stadium while dramatically reducing its carbon footprint through adaptive reuse and the use of local, sustainable materials. The new stadium is powered by its own PV system and renewable energy sources, and features integrated water systems and strategies that are predicted to cut water consumption—typically a football stadium's single largest area of consumption—by 70%.
From ancient amphitheatres to sustainable stadiums
Like the ancient amphitheatres of Greece and Rome, the original 1980s stadium was built into the hillside. The renovation retains the original concrete bowl and utilises it as the primary load bearing structure. Around the upper edge of the old stands, a continuous “boulevard” connects all sides of the stadium and provides a base for rectangular stands, where 6000 new seats made from the recycled plastic of the original stadium’s seating can be found.
The architects explain that this is the most efficient geometry for the site: “Rather than curving and obstructing visibility, the corners were transformed into distinctive features that mark the building's entrances and provide spectators with unique spaces.”
Five new floors have been integrated to the main stand that houses press facilities, commercial spaces and offices for logistics and security. The locker rooms have been expanded, VIP suites added and a range of multipurpose spaces created, allowing the stadium to be utilised for purposes other than football matches and concerts.
Built from recycled steel and locally-sourced wood
The new structure is built from reinforced concrete and steel recycled from the original stadium, the roof from wood and steel, and the exterior envelope is made from 1,600 m³ of locally sourced Chilean radiata pine glulam, which captures more than 1,500 tonnes of carbon. This envelope gives the stadium a distinctive character while serving a range of important functional purposes: reducing glare, controlling noise and improving ventilation.
The vertical glulam panels are configured for the different conditions of each side of the stadium. On shaded elevations, the main panels are spaced to admit light and airflow, while on sun-exposed sides, secondary angled slats are inserted in these spaces to provide shading and limit heat gain. On façades exposed to higher noise levels, translucent panels are integrated between the slats to reduce sound transmission without compromising daylight.
Water-saving measures and renewable energy
The largest operational demands of a football stadium are traditionally power and water. IDOM’s stadium will be powered by 436 roof-mounted solar panels from Enel X, supplemented by a 100% renewable energy supply. To enhance sustainability, the design includes water-saving measures such as greywater reuse and the replacement of natural grass with synthetic turf. According to WSP, the sustainability consultants for the project, these systems are expected to reduce water consumption by up to 70%, with the new pitch alone projected to save 120,000 litres of water per day during summer.
Bringing nature back to the stadium's doorstep
The design also incorporates the planting of native, drought-resistant trees around the perimeter of the stadium. Thousands of Quillay, Maitenes and Peumos—plants adapted to the dry conditions of Chilean sclerophyl forests—will bring the biodiversity of the Andes to the stadium’s doorstep. Requiring less irrigation, they also make the stadium’s landscaping more sustainable, supporting IDOM’s goal of creating a stadium that is not only larger and more versatile, but also significantly more environmentally friendly.
