VEGETATIONAL BASE FOR GREENING ROOF OR ROOFTOP, VEGETATIONAL STRUCTURE AND METHOD FOR GREENING USING THE SAME OR SYSTEM FOR REUTILIZING RAINWATER

摘要

PROBLEM TO BE SOLVED: To obtain a vegetational base capable of preventing earth and sand from sliding with rainwater, reduce the weight load on a building, simply carrying out laying and performing the greening execution of a roof or the rooftop at a low cost and to provide a method for greening and a system for reutilizing the rainwater using the vegetational base. SOLUTION: This vegetational base for greening the roof or the rooftop is a thermoplastic resin fibrous structure having =90% porosity, 5-100 kg/m3 apparent density and 20-100 mm thickness. The method for greening the roof or rooftop comprises carrying out the greening with a vegetational structure prepared by including a mixed soil of peat with a lightweight soil in (4/6) to (1/9) volume ratio in the vegetational base and rearing plants. The system for reutilizing the rainwater is capable of purifying the rainwater with the vegetational structure.