Biodiversity / Food / Water

October 31, 2005


Rooftop Greenery Area Up 2.6 Times in Five Years in Japan

Keywords: Ecosystems / Biodiversity Non-manufacturing industry 

The area of rooftop greenery installed in Japan in 2004 expanded to 22.3 hectares from 8.5 hectares in 2000, bringing the total area installed over the five years to 78 hectares, according to a June 30, 2005 release by the Ministry of Land, Infrastructure and Transport (MLIT). This findings is based on its survey of 249 firms, including landscape construction companies, general contractors, and rooftop greening-related distributors and installers, with responses from 149 companies.

Of all the prefectures, Tokyo had the largest area with about 23.7 hectares, or 30 percent of the national total. In second place Kanagawa, Osaka, Aichi and Hyogo prefectures each has more than five hectares of rooftop greenery.

According to the survey, rooftop greenery has been spreading particularly among residential buildings, including apartment houses, with an increase of more than 20 percent over the past five years. Similarly, rooftops of public facilities, such as educational and cultural institutions, medical and welfare centers, and commercial facilities, have shown a large increase in rooftop greenery. As for the types of vegetation planted, a mix of a variety of plants, including shrubs and trees, accounts for roughly 34 percent of the total area installed over five years. Planting of Sedums, or succulent plants which rarely need watering, also accounts for about 34 percent, and turf-based planting is nearly 21 percent. The use of turf itself increased nine times in five years since 2000, while that of sedum quadrupled.

Posted: 2005/10/31 09:09:57 AM
Japanese version