Installation site : Tollgate, parking area

Hanshin Expressway's initiative to adopt a rooftop greening system

Previously unused at Hanshin Expressway, the rooftop greening system was adopted in order to make an environmentally friendly rooftop for buildings and tollgates. Regarding its installation, the rooftop greening system consists of cultivation greening plants in trays and efficiently placing the planting trays on a folded-plate. Thus, building reinforcement and irrigation equipment are unnecessary.
Using rooftop greening, in addition to reducing the heat island phenomena in the city, this process also provides a landscape for the city and removes the heat-load on the building.

At Nakajima parking, rooftop greening was implemented on the roof of the toilet where the air conditioning equipment is not installed for the purpose of improving heat insulation and ameliorating of the scenery from the second floor of the building .

In addition, rooftop greenery has been implemented for Morishouji Mini parking as well, for the purpose of improving heat insulation, ameliorating of the landscape in the city, and improving the environmental consideration in the area beside the road.

Nakajima parking exterior
Nakajima parking rooftop
Morishouji mini parking rooftop

Greening the tollgate

Regarding the tollgates, the rooftop greening was set up mainly in urban areas in order to create the landscape in the city and to ameliorate environmental considerations in the areas beside the road.

Ōhiraki toll gate
Ogimachi toll gate
Amagasaki Nishi Tokyo

Result and construction plan

Achievements and Future Developments

Currently, rooftop greening was used on 8 buildings of the tollgate and 26 places in total. In future, we are planning to further promote greening in order to improve environmental considerations by carefully examining the site conditions, etc.

In the measurement at Nakajima parking, the maximum temperature in a normal room is 58 °C, a room equipped with a rooftop greening area is 27 °C, this installation contributes to the mitigation of thermal radiation (prevention of heat island phenomenon).

Regarding maintenance and management, we are testing and examining mosses which are easier to handle in terms of "weed counter-measure "and "fertilization treatment" instead of the use of sedum from the beginning and we are working to further improve the efficiency.

Sedum
Moss
Moss (enlarged)