In the Antigone district of Montpellier, Lorillard is restoring the woodwork of the Résidence du Nombre d'Or.

Restoration of woodwork under heritage constraints

Located in the Antigone district, the Nombre d'Or residence is part of the urban development project designed in 1984 by Ricardo Bofill. This R+6 complex, incorporating tertiary premises on the ground floor, is based on a rigorous architectural composition, founded on the principle of the golden ratio.

The facade is distinguished by its precise geometric organization: vertical grids, square modules, and the presence of small muntins structuring the openings. This design imposes a strong constraint on any intervention, particularly on the exterior carpentry, a key element of the building envelope.

Designated a "Remarkable Contemporary Architecture" site in 2019, it requires an approach that complies with heritage regulations. The project owner therefore opted for an identical replacement, consistent with conservation requirements.

A technical choice between architectural fidelity and thermal performance

The original wooden window frames with 4/6/4 double glazing had limitations in terms of airtightness and thermal performanceTheir replacement is part of a logic of energy improvement, in line with current requirements, in particular those of existing thermal regulations.

The new joinery installed is made of wood (pine), with double glazing of approximately 24 mm and a thermal transmission coefficient of less than 1,3 W/m².K. They also incorporate high-performance sealing joints and, where applicable, optimized air inlets.

As an existing precast facade wall was not modified, the intervention focused on the bays, without altering the overall construction system.

One technical limitation remains, however: the obligation to reproduce identically restricts the margins for energy optimization compared to more efficient contemporary solutions, such as mixed wood-aluminum joinery.

Integration of blackout blinds compatible with the facade

The issue of shading was a significant practical concern for residents, particularly with regard to summer comfort.

Rather than external devices, which would be incompatible with the architectural composition, an internal system was chosen: a double thermal and blackout curtain in a "stone tone" color. This solution improves comfort without altering the appearance of the facades.

"The chosen solution is based on a simple response, consistent with the facade's architecture."

This compromise illustrates the need to adapt equipment to heritage constraints, while meeting user expectations.

A construction project on an occupied site with significant logistical constraints

The renovation involved 1,518 windows and doors, with an organization adapted to a construction site in an occupied areaThree teams were mobilized, achieving a rate of 16 joinery units installed per day.

The manufacturing process, carried out in a continuous flow, made it possible to produce between 70 and 100 units per week, including specific formats up to 2,40 m wide.

The intervention included an asbestos removal operation under sub-section 4 (SS4), in accordance with the French Labor Code. Asbestos-containing joints were treated by encapsulation, with strict protocols implemented in each dwelling.

• use of fixing gels
• double internal encapsulation
• limitation of fiber emissions

"A protection protocol has been implemented in each dwelling to ensure the safety of the intervention."

Just-in-time logistics adapted to a dense urban environment

The construction site is located in a busy pedestrian area, with shops and weekly markets. The lack of a storage area has necessitated a specific logistical organization.

A nearby off-site depot served as the supply base. Daily deliveries were made on a just-in-time basis, using a suitable vehicle.

Supplying the upper floors required the use of a furniture lift, while securing the surrounding area relied on appropriate devices:

• barriers and pedestrian tunnel
• continuous presence of site supervision
• compliance with regulated time slots

This organization illustrates the role of the project manager and the installation teams in the fine management of phasing and interfaces.