environment / According to a 2007 University of Hawaii study titled The Potential for Green Roofs in Hawaii, urban Honolulu has more than 10 million square feet of building rooftops that might be suitable for green roofs. The study made a case for the benefits of green roofs: to cool down buildings and lower the temperature of the urban environment, and to absorb moisture during storms by reducing water runoff. These are all compelling reasons, but Alan Joaquin of FarmRoof also wants you to install a green roof to grow food.
The inventor of The Wiki Garden–what’s essentially a garden in a bag that includes a built-in micro-irrigation system–has tweaked the product to work on rooftops, for which waterproofing and weight is a concern. Regarding his move up, he says, “the urban landscape is now larger than the rural landscape. I was looking at how much wasted rooftop space there is across the world…and it seemed crazy not to use that wasted space to be more sustainable and grow food. It motivated me to find a solution for rooftops…and alternative ways of producing food that’s more local.”
The requirements for a FarmRoof are few: a relatively flat rooftop that can handle the load of the system, access to potable water, and sunlight. Joaquin says the weight is generally not an issue because the FarmRoof system is light (5 pounds to 10 pounds per square foot) due to a special soil blend.