Isover dresses up the Super-Montparnasse tower

Located in the 15th arrondissement of Paris, in a residential area, the Super-Montparnasse Tower was built between 1965 and 1968 by the architect Bernard Zehrfuss. Classified IGH-A (High-rise residential building), it has 30 floors, including a solarium and a swimming pool on the 30th floor. Its facades, coated with glass paste, were starting to crumble and a facelift was urgently needed. But it is a completely different project, targeting energy performance and real estate valuation, which has finally taken shape ...

The 249 co-owners of this residential tower (178 occupants and 83 lessors) have seen their charges increase sharply in recent years, due to the increase in the cost of energy. When thinking about the renovation project, it therefore became obvious that an overall energy renovation had to be carried out, in order to increase their comfort, but also to reduce their costs.

An energy audit was therefore carried out by the Paziaux Engineering firm thanks to a grant from the “Co-ownership: Objectif Climat!” Program. »From the APC (Parisian Climate Agency). The latter estimated at 227 € / year the energy savings that could be achieved with an energy renovation, i.e. a halving of energy expenditure over 000 years (taking into account a 2% increase per year in prices Energy).

In order to switch from an energy label D (170 kWhEp / m²) to a label C (104 kWhEp / m²), they recommended the installation of thermal insulation from the outside, a change of joinery and installation of a CMV. The objective was to reach the level of the BBC Rénovation label while respecting the architecture and the slender proportions of the tower.

The PELEGRIN and LAIR & ROYNETTE ARCHITECTURE firms were commissioned for this project, which has now become emblematic. This is indeed the first renovation of a high-rise residential building that meets the requirements of the Paris Climate Plan.

A real work of haute couture then follows in order to reconcile the architectural quality of the tower, its finesse, its slender appearance and the search for energy efficiency. This work of drawing and proportions was decisive in the choice of insulation products. ISOVER Isofacade 32 glass wool insulation was selected for its low thickness in relation to its performance, thanks to an exceptional lambda of 0.032 W / (mK).

It was implemented in 3 thicknesses in order to reproduce the original volumes of the tower:

• In 140 mm under the sills of the current parts
• In 100 mm in the common parts
• 80 mm on the exterior faces of the loggias

Isofaçade 35 was also installed in 200 mm in the facade sections without openings.

This insulation was supplemented, at loggias level, by rock wool, Isover TF, which was also laid in 3 layers covered with plaster, in order to maintain an optimized daylight at the openings (particularly holding element at the heart of the co-owners) while maximizing thermal performance on the other sections. Isover TF was thus implemented:

• In 30 mm at the level of window panels
• In 40 mm at the level of the loggias
• In 200 mm to the right of the loggia lintels

The Isofacade 32 glass wool was finally "dressed" with an aluminum sheet cladding in 3 different colors to respect the original colorimetry: off-white, light gray and black. This non-corrosive cladding requiring very little maintenance ensures the durability of the building.

This project had to be validated by the Architects of Buildings of France, the association of Vieux Paris, the association Patrimoine XXe siècle, the architect voyer of the city of Paris and the beneficiaries of Bernard Zehrfuss.

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