A spectacular green tower ringed with trees will rise in Nantes, France as both a tribute to the city's botanist roots and a way to provide greenery and energy savings for the mixed-use complex. The new Tour Végétale de Nantes will host retail, office space and apartments, and is a full-service urban project with quality of life and energy savings at its core. Known for integrating luscious plant facades into his designs, architect Edouard Francois is raising the stakes by adding trees to the balconies, visually transforming the structure into a small mountain.
The complex is broken into two buildings that rise from either end of a block of ground floor retail. A black rubber façade covers the rectangular office building at one end, and in stark contrast a rounded residential tower rises much higher on the other side. The residential tower is ringed in balconies to provide generous outside space complete with plenty of plants.
The potential of hosting trees at all corners of the building is being carefully studied to understand their adaptive properties in mountainous environments — something that is mimicked by the building’s verticality. The Botanical Garden of Nantes is experimenting with the growth of chasmophytes trees, a rare collection of mountainous plants. The plants take root in rock fissures so the experiments are to show if the tree will also grow in elongated tubes. After a year of intensive testing, the idea is showing great promise.
Francois will attach long tubes, from 15 to 20 cm in diameter, to the balconies that will run one or more stories below. The low water plants will take root and grow to become short trees poking out from the building like a rocky hill. The added shade and greenery will create a micro-climate in the summer and the leafless trees will let in sunlight during the cold winter months.