Per 235-13: GREEN SPACE: Land area with landscaped or natural vegetation, including those vegetated areas located under upper story decks, porches and overhangs that are a minimum of seven feet from the ground at the lowest elevation.
Minimum green space requirements can be found in 235 Attachment 3, Table III- Table of Dimensional Requirements, here.
The percentage of green space can be calculated by totaling the square footage of impervious surface, dividing it by the total square footage of the property, multiplying by 100, and then subtracting the final percentage of impervious area from 100. Ex: 1500 sq ft (impervious) / 4,356 sq ft (total sq ft of property) = .344 sq ft .344 sq ft x 100 = 34.4% (percent of property that is impervious). 100% (entire property) - 34.4% (percent of property that is impervious) = 65.6% total green space.