Introduction
HVAC equipment generates noise pollution which, without appropriate treatment, exposes occupants to levels incompatible with the requirements of a higher education site. Groupe Boët provided theÉcole Normale Supérieure de Paris with a rigorous technical response to this problem, reconciling noise reduction, aeraulic performance and architectural integration under the supervision of the Architectes des Bâtiments de France.
Acoustics and heritage: combined constraints
Buildings classified as Historic Monuments or under the supervision of the Architectes des Bâtiments de France (ABF) are subject to particularly strict conditions. Any visible modification to the architectural envelope is subject to prior approval. Materials, colors, proportions and equipment layout are subject to rigorous control. In this context, standard industrial acoustic solutions – often bulky or visually intrusive – cannot be deployed without adaptation.
In addition to this heritage constraint, there is the imperative of maintaining airflow performance. Effective noise control must not be achieved at the expense of the air flow rates required for the proper operation of HVAC systems. It is precisely at the intersection of these two requirements that the complexity of the project lies.
HVAC issues at the École Normale Supérieure
L’École Normale Supérieure de Paris houses teaching, research and administrative functions in a building of great heritage value. The existing ventilation equipment generated noise emissions that were incompatible with the site’s regulatory objectives. As their complete replacement was neither feasible nor technically justified, the challenge was to integrate high-performance acoustic systems around the existing installations, in an occupied site and without interrupting activities.
The requirements of the project were therefore multiple and simultaneous: to achieve the target noise levels defined by the prime contractor, to maintain airflow rates at their nominal values, to comply with the ABF’s requirements on the visual appearance of the equipment, and to ensure total continuity of operation during the works.
Custom aero-acoustic dimensioning
Groupe Boët carried out a customized aero-acoustic design, combining noise reduction objectives with the flow constraints of the existing installations. This engineering phase made it possible to define acoustic grilles acoustic louvres, sized to achieve the required levels of attenuation without generating a penalizing pressure drop for the aeraulic network.
Integration
Architectural integration was the subject of a specific treatment: colors, proportions and layout were determined in consultation with the project management and validated by the ABF. These acoustic ventilation grilles are part of the visual continuity of the building, without any aesthetic break or major modification to the existing infrastructure. Implementation was carried out on an occupied site, with close coordination to ensure continuity of operation at every phase of the worksite.
Certifications and expertise
Groupe Boët relies on ISO 9001 and ISO 19443-certified manufacturing, in compliance with the main building codes in force: EN 15085, ASME, RCC-M, CODAP and CODETI. This rigorous production process guarantees acoustic equipment that is traceable, durable and adapted to the most demanding environments.
Results: compliance, performance and heritage integration
At the end of the intervention, the noise levels measured were in line with the regulatory objectives defined during the design phase. The aeraulic performances of the installations were maintained at their nominal values: no loss of flow was observed. Architectural integration has been validated by the ABF and the project management, without reservation.
This project illustrates the feasibility of comprehensive noise control in a multi-constrained environment, without compromising on technical performance or heritage requirements. The solution deployed is sustainable and requires no structural modification of existing infrastructures.
Acoustic expertise for complex projects
This project atENS Paris confirms that dealing with noise in constrained environments requires a rigorous engineering approach, right from the design phase. Groupe Boët works on projects with a combination of regulatory, heritage and technical constraints, providing customized industrial acoustic solutions from design to commissioning. To submit a similar project, contact Groupe Boët and benefit from an acoustic analysis tailored to your constraints.