The balconies
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From the initial realisation of the Clarté building, the balconies had proved problematic. Initially projected at the same height on the north and south facades, they were finally constructed at different heights on each facade. They had not been accurately costed in the initial budget, and hence economies were made in their construction, resulting in many technical faults. During the building’s construction, an expert report of 10 February 1932, directed by the engineer Maurice Brémond 6, stated that the structural design of the balconies was “permissible, though not satisfactory” and that the long-term performance was not adequate regarding environmental exposure. Maurice Brémond even indicated that fracture of the welded “C” brackets, used to secure
the balcony floor to the parapet, or rupture of the latter, could have serious consequences. Originally, the balconies were formed from 76 centimetre high load-bearing frames, comprising the balcony parapet and consoles (end-plates), having a width of 1.50 metres at the second, third, fourth, fifth floors and a width of 1.85 metres at the sixth and seventh floors. The consoles were welded to a vertical facade support at every 8.40 meters; all elements being built of strong sheet steel (consoles: 5 mm thick; parapets: 3 mm) reinforced with flat steel bars (section – 60 × 5 mm) and L-shaped steel bars (60 × 40 × 5 mm). The parapet plates were reinforced at two intermediate points (2.8 metres apart) by stiffening gussets 7 fixed to the balcony floor. The wooden floor slats were supported
by two UPN 80 channels, one against the facade welded to its vertical supports, the other forming an edge beam, suspended every 2.80 metres from the parapet plate by C-shaped steel hangers, called “swan necks” (approx. 100 × 220 × 40 × 12 mm). The two channels were laced every 1.40 metres by tensioned 16 mm steel rods passing through 25 mm diameter tubes. The ceilings of the original balconies, covered with smooth panels, had suffered significant water damage. These panels were removed during the intervention by Mark-Joseph Saugey in the 1950s. Following the 1975–1977 restoration, the floors comprised 40 mm thick slats of larch wood (originally oak), with a grooved and caulked 8 upper surface, oriented perpendicular to the facade.
1 Cross-section showing the balcony offset between north and south facades. 2 West gable-end facade with travertine cladding, after works. 3 South facade, fourth floor, before works, 8 October 2007. 1
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