The database on roofing provides information on the types of rooftop material used. Information on four groups of material is gathered for each rooftop based on the analysis of aerial photographs: surfaces made of zinc or other non-determined material, mineral surfaces such as concrete, tiled surfaces and planted, greened surfaces.
Based on the exact surface area of these four groups of material, a predominant material is given to each rooftop. This results in the following, average proportions of all Parisian rooftops:
- 78% of rooftops are predominantly zinc or other material
- 12% of rooftops are predominantly mineral (concrete etc.)
- 7% of rooftops are predominantly tiled
- 3% of of rooftops are predominantly greened
