Zinc Roofs of Paris

The grey roofs of Paris, sheathed in zinc and slate and punctuated by chimney pots and dormer windows, are one of the world's best-known urban roofscapes. They largely date from the transformation of the city in the mid-19th century.

Origins

Metallic zinc became available as an industrial building material in the early 19th century. In 1806 the Napoleonic authorities granted the Belgian industrialist Jean-Jacques Dony the right to work the zinc deposit at La Vieille Montagne near Liège. The Société des Mines et Fonderies de Zinc de la Vieille-Montagne, founded in 1837, became a major producer of rolled zinc for building. Its rolled-zinc business continues today under the VMZinc brand, now part of Umicore.

The Haussmann era

The typical Parisian combination of zinc, slate and green-tinged metalwork became established under Napoleon III's Second Empire (1852-1870), during Baron Haussmann's rebuilding of the city. Haussmannian apartment blocks spread quickly along the new boulevards. Zinc suited them well: it was inexpensive, easy to cut, solder and form, and light enough to allow lighter roof frames over the mansard attics that the building rules encouraged.

Mansards and height rules

A 1783 rule limited Paris buildings to a height of 20 m (66 ft) measured to the cornice, so space inside a roof did not count. Mansard roofs, steep on the lower slope and shallow above, created extra rooms within the roof. A 1902 revision allowed three or four storeys within the roof envelope. Zinc covered the flatter upper slopes and many of the dormers.

The roofers

The roofs are maintained by couvreurs-zingueurs, roofers who cut, solder and fit zinc and slate.

UNESCO proposal

Since 2014 the roofs of Paris have been the subject of a proposed World Heritage inscription. The Paris Council approved the project in October 2014, and a support committee was launched on 5 February 2015.

Legacy

The Paris roofscape is closely tied to the mansard form named after François Mansart and to the rolled-zinc industry that grew up in Belgium in the 19th century. Zinc remains a widely used architectural roofing metal.