Kajima / Providing solutions that contribute to biodiversity, making maximum use of building greening technology
Concept and application example of rainwater storage and infiltration type greening system (from press release materials)
Kajima provides comprehensive solutions that contribute to biodiversity and rainwater storage and infiltration. Developed 3 technologies: exterior green space system "DEW Rain Garden", rooftop greening system "Eva Cool Garden" improved from existing technology, and wall greening system "Rokusai Multi Panel.RT". We adopted the three technologies for the first time in our facility. We will maximize biodiversity and reduce the amount of rainwater that flows out of the site by making the most of the greening technology for the building exterior, roof, and walls.
The DEW Rain Garden is highly effective in storing and infiltrating rainwater, and by adjusting the water retention capacity of the excavated soil, it enables the growth of various plants. Birds and insects gather in search of flowers and fruits, leading to biodiversity.
Rainwater quickly penetrates into the soil layer and temporarily stores water in the crushed stone layer with many voids below the soil layer. Penetrates gently into the ground. It can reduce the load of drainage from the site to the sewage system during heavy rains and suppress the rainwater flowing from the ground surface to the surrounding roads. Outdoor demonstration tests have confirmed that DEW rain garden soil has four times the rainwater storage capacity of general exterior soil in the case of a highly permeable soil structure and rainfall equivalent to 100 mm per day.
Ever Cool Garden is a rooftop greening system that stores rainwater and promotes evapotranspiration. The water retention capacity of the lightweight soil "Keisoil" developed by the company was improved, and combined with the reservoir, the amount of rainwater stored was increased. It also contributes to the mitigation of the heat island phenomenon.
A green multi-panel. RT is a rainwater storage panel type wall greening system in which a rainwater storage tank is newly installed on the back of the existing green multi-panel. It achieves excellent design while securing rainwater storage capacity.
For the first time, the company has adopted the three technologies simultaneously in the construction of its own facility. In the future, more detailed monitoring and evaluation will be carried out, and the technology will be disseminated and deployed. We will further improve performance and contribute to the realization of regional disaster prevention and mitigation and the restoration of nature (Nature Positive).
