Toitures
L'architecture peut-elle continuer à réinventer le paysage des toits ? Depuis 2019, nous le savons. Cette année-là, Bjarke Ingels a transformé le toit en pente de 400 m d'une usine de valorisation énergétique des déchets de Copenhague en une piste de ski verdoyante. Depuis, environ 10 000 sportifs gravissent chaque année CopenHill, la plus haute colline du Danemark, pour redescendre en douceur. Ce concept ne peut être reproduit partout, mais il révèle le potentiel latent des toits comme terrains urbains d'aventure – des espaces bien trop précieux pour être laissés à l'abandon sous des couches de bitume à l'ère du changement climatique. Les projets d'habitat coopératif et de cohabitat ont depuis longtemps adopté les toits-terrasses communs comme lieux de jardinage, de rencontres sociales et de séchage du linge, tout en contribuant à lutter contre l'effet d'îlot de chaleur urbain et la perte de biodiversité.
Le mouvement s'étend désormais du logement à l'immobilier de bureaux, les géants mondiaux de la technologie étant une fois de plus en tête. Il y a dix ans, Frank Gehry transformait le toit plat légèrement ondulé du campus Facebook à Menlo Park en un parc de 3,5 hectares surplombant le lagon. Google lui emboîte aujourd'hui le pas au cœur de Londres. À King's Cross, l'achèvement du bâtiment BIG et Heatherwick Studio se faisait attendre année après année. À Berlin, les choses ont été plus rapides : sur Darwinstrasse, Grüntuch Ernst a réalisé un parc sur le toit de 2 200 m² surplombant 1 000 postes de travail. S'élevant en cascade sur quatre étages, il est directement relié aux bureaux en open space par des baies vitrées coulissantes. La terrasse est également ouverte sur le quartier, dynamisant ainsi le quartier. Une vision des toits non pas comme des surfaces résiduelles, mais comme des espaces urbains partagés.
Roofs
Can architecture keep reinventing the roofscape? Since 2019 we know it can. That year, Bjarke Ingels turned the 400 m sloping roof of a waste-to-energy plant in Copenhagen into a grassy ski slope. Since then, around 10 000 sports enthusiasts have made the annual climb up CopenHill, Denmark's highest hill, to glide back down. The concept cannot be replicated everywhere, but it reveals the latent potential of roofs as adventurous urban terrains – spaces far too valuable to be left to languish under layers of bitumen in an age of climate change. Cooperative housing and cohousing projects have long embraced the communal roof terrace as a place for gardening, social gathering, and drying laundry together, while also helping to counter the urban heat-island effect and loss of biodiversity.
The movement is now spilling over from housing into office real estate, with global tech giants again leading the way. Ten years ago, Frank Gehry shaped the gently undulating flat roof of the Facebook campus in Menlo Park into a 3.5 hectare parkland above the lagoon. Google is now following suit in the heart of London. At King's Cross, completion of the BIG and Heatherwick Studio building has been awaited year after year. In Berlin, things moved faster: on Darwin strasse, Grüntuch Ernst have realised a 2200 m² roof park above 1000 office workstations. Cascading across four storeys, it connects directly to the open-plan offices through sliding glass doors. The terrace is also open to the wider neighbourhood, enlivening the district. A vision of roofs not as residual surfaces, but as shared urban ground.
Can architecture keep reinventing the roofscape? Since 2019 we know it can. That year, Bjarke Ingels turned the 400 m sloping roof of a waste-to-energy plant in Copenhagen into a grassy ski slope. Since then, around 10 000 sports enthusiasts have made the annual climb up CopenHill, Denmark's highest hill, to glide back down. The concept cannot be replicated everywhere, but it reveals the latent potential of roofs as adventurous urban terrains – spaces far too valuable to be left to languish under layers of bitumen in an age of climate change. Cooperative housing and cohousing projects have long embraced the communal roof terrace as a place for gardening, social gathering, and drying laundry together, while also helping to counter the urban heat-island effect and loss of biodiversity.
The movement is now spilling over from housing into office real estate, with global tech giants again leading the way. Ten years ago, Frank Gehry shaped the gently undulating flat roof of the Facebook campus in Menlo Park into a 3.5 hectare parkland above the lagoon. Google is now following suit in the heart of London. At King's Cross, completion of the BIG and Heatherwick Studio building has been awaited year after year. In Berlin, things moved faster: on Darwin strasse, Grüntuch Ernst have realised a 2200 m² roof park above 1000 office workstations. Cascading across four storeys, it connects directly to the open-plan offices through sliding glass doors. The terrace is also open to the wider neighbourhood, enlivening the district. A vision of roofs not as residual surfaces, but as shared urban ground.
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