The soothing effect of a cocoon


It took three years of work carefully programmed to avoid interrupting reception operations, for the reception area of the new Mother and Child building of Troyes central hospital to achieve its very distinctive feel. Architects Hérard & Da Costa, who won the commission by setting out to improve the flow of visitors in the existing space, incorporated a clear separation of flows in their design. A large exterior awning sets off the entrance to the reception hall of the Mother and Child unit, which opens out into a larger area, since the architects moved certain other functions elsewhere. The 400-sq. m (4,300-sq. ft) space makes the reception area feel much larger despite its low ceiling. A feeling of cosy protection is produced by the installation of a Strato open-knit fabric ceiling, specified by the architects.

The architects imposed a strict pattern for the fabric ceiling, because their design provided for precisely sized pipework and ducting allowing the full height of the plenum space to be visible through the Strato knit. Artificial lighting hanging 30 cm above the open knit ceiling obviously lends a three-dimensional appearance to the structure. However the impression of cosiness that the area exudes, is also produced by the acoustic quality of the installation. Firstly, the frames of the Strato modules are fitted with sound absorbing foam which achieve a coefficient of around 0.15. Secondly, a thick layer of absorbent black flocking was applied under the roof to mute the echo that untreated concrete would have generated.

Specifying this modular fabric ceiling was not an easy matter. Compared to the initial metallic solution, the fabric ceiling had several advantages in its favour. The product is perfectly hygienic, not electrostatic, it doesn’t hold dust and is easily cleaned, so it was rational to specify it for a healthcare and treatment centre. The mechanical strength of the knitted fabric and the simplicity of the zipper openings enabling the fabric to be pulled back for service personnel to insert their head up into the plenum space, were plus points for maintenance staff, who were surprised by the ease with which the large, light modules could be handled. It was however the safety department that really put the ceiling through its paces to ensure that Strato would not hinder the evacuation of smoke in the event of fire. A full-scale test was demanded and carried out, proving that the large open-knit fabric was no obstruction to warm smoke. The modules carefully hung by installers Berriot Linselle were not blown out of place by the powerful smoke extractor fans. The product ended up ticking all the verification boxes.

Now that items of red furniture are arranged on the light-coloured floor and their appealing silhouettes are projected crisply on the white walls, the dark ceiling goes beyond its technical role and asserts its architectural importance. The fabric forms a kind of canopy that is perfectly transparent when you look up from a position vertically below it, but it becomes progressively more opaque as your line of sight is more and more slanted. The grey-brown hue filters the artificial light without restricting the actual illumination produced. A hollow seal around the periphery adds a touch of refinement to the surface of the ceiling, which, again, is not marred by any structural profiles.

This first major public works implementation in Troyes heralds further development of Strato breathing ceilings in France.


144 Strato modules used to form the seven sections of ceiling in the reception hall of the Mother and Child building.

Total area installed: 388.2 sq. m
(4,178 sq. ft)
Principal: Troyes central hospital
Architects: Hérard & Da Costa
Installer: Berriot Linselle
Photographer: Clément Guillaume