Rooftop Greening Equivalent to Three National Stadiums in 2025
Overview
According to a Ministry of Land, Infrastructure, Transport and Tourism survey, rooftop greening installed in 2025 covered approximately 21.9 ha, while wall greening covered approximately 4.8 ha; the rooftop area is equivalent to about three National Stadiums. From 2000 through 2025, cumulative installed areas were approximately 656 ha for rooftop greening and 137 ha for wall greening. Recent examples of green infrastructure are also presented, including projects designed to reduce runoff through rainwater storage and infiltration and to support biodiversity.
Key points
- In 2025, installed areas were approximately 21.9 ha for rooftop greening and approximately 4.8 ha for wall greening.
- From 2000 through 2025, cumulative installed areas were approximately 656 ha for rooftop greening and approximately 137 ha for wall greening.
- Recent notable trends include examples of green infrastructure.
Overview
Rooftop and wall greening help mitigate the urban heat island effect, create attractive and comfortable urban spaces, and decarbonize cities, and efforts are advancing nationwide.
Since 2000, the Ministry of Land, Infrastructure, Transport and Tourism has surveyed rooftop and wall greening projects nationwide and compiled the results of its 2025 survey.
Details
The rooftop greening installed in 2025 covered an area equivalent to about three National Stadiums. The National Stadium covers approximately 6.96 ha.
The survey was conducted by postal questionnaire. It covered 573 companies nationwide, including landscaping construction firms, and received responses from 280 companies. The response rate was 48.9 percentage points, and the survey period was January 1 through December 31, 2025.
The cumulative figures cover 26 years of installations from the start of the survey through 2025. Respondents were asked to provide data going back up to three years, so the data for 2024 and 2025 are provisional and may change based on surveys conducted from next fiscal year onward.
Recent notable trends include green infrastructure projects that make use of extensive green spaces and advanced greening technologies to reduce runoff through rainwater storage and infiltration and to support biodiversity. Examples include Common Nexus, a university facility operated by the Tokai National Higher Education and Research System, which features large-scale rooftop greening with water recharge functions, and Azabudai Hills, a large commercial complex with large-scale rooftop greening over complex curved surfaces.