Germany and Europe?s largest airport, Frankfurt International (FRA) is ranked no. 7 in the world. At 20 square kilometers (4,942 acres) in size, FRA is also one of the most compact of the larger world airports. As a result, one of Frankfurt International?s key issues is ecological land conservation as they strive for optimum land use with minimal negative environmental impacts in the densely populated Rhein-Main region.

Information on Frankfurt International (FRA) is provided here as a whole for the entire airport area, as individual roof figures are not presently available.

The total estimated airport area greenroofed at FRA since 1990 is 40,000 m2 or 430,556 sf with between 20 to 25 greenroofs in total. The sizes of greenroofs range from 17,000 m2 (182,986 sf) to 100 m2 (1076 sf) (Fraport AG). FRA Terminal 1 holds the largest extensive greenroof at 17,000 m2, which is 15 years old (as of 2005).

Fraport has installed numerous greenroofs during the last 15 years on different types of buildings, including on the two terminal buildings, the tower office building, maintenance, cargo and other office buildings. A few roofs were designed for use and visibility by the public, and some are visible only from overhead buildings. Plants are also used extensively on building facades, within inside courts and on top of the terminal roofs. Planning and upkeep are usually handled by airport specialists who run their own airport greenhouse shops

Optigr?n / Optigreen estimates having greened about 11,700 m2 (125,938 sf) of the total. Optigr?n estimates that 2,400 m2 are intensive, and the rest are extensive greenroofs. Optigr?n has used the following substrates depths for these greenroofs: Intensive: (40 ? 60 cm 16 ? 24?); Extensive 8 ? 10 cm (3 ? 4?).

Vedag waterproofing systems (see below) says that in 2007, the greenroof on Terminal 1 was renewed together with the entire roof build-up. ?The greenery is ecologically of great value as it improves the overall climate of the Terminal,? says Bernd Beuchert, Director of Green Area Management at the airport. The roof offers a place of refuge for plants and animals and the greenery serves to protect the roof covering. ?The plants actually help to double the life expectancy of the roof,? says Fritz Hammerle, Agricultural Engineer and Green Roof Specialist.