Located in Rennes, the new DFRS (Departmental Fire and Rescue Service) of Ille-et-Vilaine (France) is a 7800m² complex made up of a 170-meter-long building, with a 30 meters high office tower.
The main characteristic of the new DFRS is the red-orange color and the many openings that compose it. The central tower was cast in place, while the 450 prefabricated panels were specially designed to allow to combine specific visual characteristics and high mechanical stresses, such as resistance to seismic shocks.
The production of 450 prefabricated panels, mostly in the 9-meter by 3-meter format, required a high level of expertise to meet these constraints. The outer skin of the panels, 8cm thick and tinted in the mass, had to prevent cracks during stripping while maintaining a very high quality of finish.
The prefabricated panels, heavily reinforced to compensate for the large number of openings in the building facade, were designed for vibration-free casting and required the use of class S5 fluid concrete. The pouring speed could not exceed 85 cm per hour to obtain a homogeneous distribution of the concrete.
To guarantee the red-orange color, a specific process has been implemented: The formwork bottoms were cleaned using high pressure gas at low temperature in order to avoid scale deposits. Once the concrete facings were made, they were steamed to prevent carbonation's trace at early age.
Project management: department of Ille-et-Vilaine.
Project management: LAN Architecture (agent).
BET: Terrell (structure and fluid), Jean-Paul Lamoureux (acoustics), Bureau Michel Forgue (economist), Most (architect of execution works), Casso & Associés (SSI coordinator), Best (synthesis).
Company: Angevin (demolitions, foundations, earthworks, structural work)