The ecological renovation of the Montparnasse tower (France)
A super-passive tower
A smart-grid-ready & symbiotic tower
A positive energy & ultra-low carbon tower
An innovative & frugal tower
Elioth, an Egis group subsidiary, took out top spot in the competition for the renovation of the Montparnasse Tower, alongside Nouvelle AOM, a collaboration between the three French agencies Frank Linazzi , Chartier-Dalix and Hardel & Lebihan
In 2030, the city of Paris will be able breathe again. In complete sync with the climate, the wind, and the light of the sky, Montparnasse tower will become a symbol of its time. “Super-passive”, the building joins the ranks of the world’s most efficient new builds. And it is even set to overtake them in terms of its carbon footprint, by saving on resources required for its reconstruction. This is a virtuous tower – an oxymoron made possible through the choice of its rehabilitation and extension of the lifespan of its structure and foundations, the building elements that generate the most greenhouse gas during construction.
With this very first, energy positive and low carbon renovation, following the removal of all asbestos Montparnasse Tower will reduce its energy consumption by 10 compared to the original project. It will be self-sufficient for 70% of the time it is in use, during which time it will not draw on any active systems and simply glide along. In addition to being exemplary for its energy efficiency, it will also be beautiful, standing tall with its ever-changing and light-filled “weather-coloured” exterior. This ultra-contextual and symbiotic Parisian tower will blend seamlessly into its neighbourhood, improving urban air comfort and promoting the mutual benefits of energy complementarity, including with the train station and future developments in the area.
“The future Montparnasse Tower will be multifunctional, active 24 hours a day and exemplary when it comes to the environment, with a tenfold reduction in its current energy use. It will be the world’s first “wind tower”, capturing wind energy and minimising mechanical ventilation. Finally, 80% of the existing façade will be re-used inside the tower, magnifying its heritage.”
The design of the façade rests on two key concepts: on both side of the building hanging gardens will be constructed. The first ten floors of offices will have conservatories, with outside access provided along vast balconies. These spaces bring an almost homely touch to the lower office, and create an urban feel through their dialogue with the environment around the Tower. They also reduce wind at the base of the tower, improving the urban comfort of the surrounding area.
The other element which will improve public space through marginally adjusting the existing layout, is the establishment of large tree-covered patios at each of the four corners of the site. Anchoring the Tower even deeper into the Parisian soil, they reduce the “downwash” wind effect, bringing comfort to the esplanade and helping guide pedestrians between the Rue de Rennes and the future train station. The wind tower, this “Eole-Montparnasse”, is a designed to look after us, both inside and out.