Method and system for storing water inside buildings

A method of collecting and utilizing rain water stored in a building structure between an interior and an exterior waterproofed wall system, the method comprising:

• providing a building catchment system;
• the catchment system comprising a building with multiple side walls forming a parameter;
• a green roof having plants, the roof collects and filters rain water;
• an impurity filtering system for the rain water in addition to the green roof, the filtering system being the media by which the plants grow;
• a channeling system that moves the filtered rain water into the building walls;
• each of the side walls comprised of a waterproofed inner wall and a separate outer wall with a void space between, the inner and outer walls forming a wall system;
• the entire area of the void space between the inner and outer waterproofed walls is available for rain water storage;
• the void space between the walls does not include or require pipes or containers to hold the water between the walls;
• a pump system that moves the stored water, between the waterproofed inner and outer walls to provide potable water for interior and exterior applications;
• a temperature regulating device that allows the stored water to create and maintain ambient temperature within the building structure;
• an overflow device at the top of the wall system;
• exterior outlets for flushing the stored rain water out of the building walls;
• provide a flush by-pass valve to allow a pre-determined amount of water to flow into the void space.