Atypical finishes on the large facades of the Moulin Vert residence in Sannois (95)

With its 287 apartments, the Moulin Vert residence in Sannois (Vald'Oise) is one of the largest housing estates of the Ile-de-France social landlord Immobilière du Moulin Vert (SAIMV). Between 2017 and 2018, its five R + 3 and R + 4 buildings were renovated to improve their energy performance.

60s bar

The freestone buildings were built in the 1960s. Since then, the facades have not changed. Before the rehabilitation, the dwellings display an energy label E (consumption of 231 to 330 kWh / m² year).

The objective is to reach level C (91 to 150 kWh / m² year). The work program includes the realization of thermal insulation from the outside, the installation of a new boiler room and ventilation systems in the homes, as well as the replacement of exterior joinery and repair of the roof.

Alexandrin Chorao, director of ECI Management, is entrusted with the project management of the operation. To break up the image of the bars of the 60s and better identify the entrances, he draws dark-colored vertical faults at the level of the halls, which contrast with the white of the running parts. And to add relief to these white walls, each floor nose will be highlighted by a horizontal metal profile in the same shade as the plaster.

A whole range of finishes

On the technical side, the architect chooses for the current parts an external thermal insulation system StoTherm Mineral 1 consisting of a coating applied to rock wool panels 160 mm thick wedged-dowel.

"This non-combustible insulation is used more and more for the energy renovation of housing", underlines the architect.

For the finishing plaster, he recommends Stolit Milano with a sanded concrete appearance.

As for the vertical faults to the right of the entrance halls, they will be made of ventilated cladding to be coated with StoVentec R. Here again, it is the Stolit Milano coating which is retained, but with a Marmorino aspect and completed by a coating in StoColor Metallic paint in brown color. Since the cladding is ventilated, it can withstand a dark tint without the risk of excessive heating under the effect of solar radiation.

Finally, the guardrails which have a masonry part will be coated with a D3 reinforced Stolit MP plaster with a smooth finish, the deep gray color of which (reference 79203) justifies the contribution of X-black technology. This system made up of a fiber-reinforced underlayment, a fiberglass frame and a traditional structured finish will provide better resistance to these cracked elements with plaster detachments.

Patient implementation

For the GCEB company in charge of the facades batch, the Marmorino finish is a first “really atypical and special”. For Daniel Mendes, project manager, the help with the implementation was welcome:

“Sto offers very innovative products and accompanies us on the site to implement them. In Sannois, we produced a witness at the architect's request. A Sto technician came to assist us to start the realization of these atypical finishes. "

To obtain the concrete aspect of the plaster on insulation, several steps must be linked. After the StoLevell Uni base plaster with its mounted glass cloth, the finishing stage begins with the application of a layer of Stolit K1.5 with a float. After drying, the Stolit Milano plaster is in turn applied by holding the float more inclined than for a traditional application and by scraping lightly. The gesture is straight, short and crossed for a slightly striated texture. In the days that follow, once the surface is completely dry, you can proceed to sanding.

"A long step which must be carried out when the plaster is dry but not too dry, otherwise it becomes too hard"remembers Daniel Mendès.

pastillage

The Marmorino aspect is obtained by depositing the Stolit Milano plaster by random pastillages which provide reliefs reminiscent of traditional Mediterranean facades.

The application of the Stolit Milano plaster is carried out with a stainless steel float in two or three passes. The first is an equalization layer. After drying, if necessary, and in order to eliminate any unevenness, a second coat is often necessary. Finally, the pelletizing operation consists in randomly depositing small quantities of StolitMilano in order to recreate a relief. Sto technicians then advise to felt the product with a slightly damp sponge in order to remove the trowel strokes and spatula burrs which remain visible.

The facade insulation work was completed by the application of a Sto-Polydal liquid waterproofing to the balcony slabs, carried out by the same company GCEB.

Both the residents of the residence and the owner are satisfied with the transformation.

"In all our rehabilitation operations, we give priority to quality materials that last over time, for a controlled budget., underlines Pierre Bainson, asset and proximity manager of SAIMV. On this residence, we carried out an energy audit of the various proposals. The one we chose offered the best value for money. "