A Community Garden on a Parking Garage
Posted in Models by Kate Archdeacon on July 6th, 2012
Source: The Atlantic Cities
Photo by Nicole Kistler
From “A 30,000-Square-Foot Community Garden, in a Parking Garage” by Sarah Deweerdt:
[Seattle] residents are building a 30,000-square-foot community garden atop a two-story structure once intended for fair visitors’ cars.
“As far as we can tell it’s the first community-managed food production garden on a rooftop” in the country, says Eric Higbee, a landscape architect working on the project. This project, dubbed the UpGarden, will have space for about 120 gardeners. There are a few rooftop farms, such as Eagle Street Rooftop Farm in Brooklyn. But a commercial operation like that runs around $10 per square foot to construct, while the UpGarden has shoestring budget of $4 per square foot—and it’s designed to be built and maintained almost entirely by volunteers.
The project came about because Seattle’s P-Patch community gardening program was looking for space to build a new garden in the neighborhood. “We were really struggling, because the neighborhood is really dense,” says P-Patch coordinator Laura Raymond.
But building a rooftop garden isn’t straightforward. “You’d think that cars are really heavy, and you could put anything on top of a garage,” says Nicole Kistler, a landscape designer and artist also on the design team. In fact, soil is much heavier—12 inches of water-saturated soil can weigh over 100 pounds per square foot, but the garage is only designed to support 40 pounds per square foot.
“We had to find a way to get enough soil up there to grow vegetables, but also not exceed the weight capacity of the garage,” Higbee says. “That really drove a lot of the design decisions.”
Typical green roof technologies were too expensive, so they settled on a series of wooden raised beds 12 to 18 inches deep, which will be filled with potting soil. It’s lighter than topsoil. Higbee and Kistler also left wide paths between the garden beds.
At $150,000, designing and building the UpGarden will cost about 10 percent more than a ground-level community garden of similar size, Raymond estimates. The increased costs come mainly from a longer, more elaborate design process, the need for a structural engineer, and a contractor to drill into the garage deck. In addition, the low clearance of the garage means that materials like potting soil and wood chips will have to be blown in, rather than a large load being dumped by a truck and wheelbarrowed into place by volunteers.
Read the full article by Sarah Deweerdt for more details.