April 28, 2009
A Living Wall
When the new Whole Foods store opens to the public this Wednesday at Broadway and Cambie, there will be plenty of evidence inside that supports the grocery retailer's planet-friendly mandate. But before you rush inside, stop to take in the “Living Wall” which adorns the north facing wall of the building on 8th Ave. It is, literally, the green form of urban architecture that could become the colour of future cityscapes -- from that of industrial grays and sterile glass, to one with more verdant, natural hues.
While we've noted several recent examples of the “greenification” of Vancouver’s rooftops (see links below), and applauded a number of civic-minded efforts to plant gardens over asphalt lots, other than the green wall designed for Joe Fortes new rooftop garden reno, this is the first time we’ve seen plants applied vertically to a structure’s walls. (Unless of course, you count the cascades of ivy tumbling down the sides of the old Sylvia Hotel.)
The work of architects Busby Perkins + Will and Eckford & Associates, the project is a sculptural marvel of engineering that is based on the standard drip irrigation system commonly used in vineyards and other forms of field agriculture.
To create the wall, BC native plants such as huckleberry, euonymus, and licorice fern were individually placed within self-contained soil “panels”, which were then mounted on a frame attached to the side of the building. The placement of these panels will allow the plants to be watered from a network of hidden pipes that connect cell to cell using gravity for downflow and a pump mechanism to circulate the water back up to the top of the grid again. (Somewhat in the same way that fountains function.) Water is held in three 15,000 gallon cisterns (partially collected from rainwater), that are located under the sidewalk along Broadway.
Planted in horizontal rows to create bands of green that vary in colour and texture, the result is a living work of landscape art, that beyond the obvious aesthetic, also boasts an ecologically useful purpose. The system utilizes the plants’ natural photosynthesis to remove CO2 smog from the air and replace that with clean oxygen. The Whole Foods wall alone is estimated to be able to pump some 2,700 litres of oxygen per hour back into the atmosphere.
Another bonus -- as plants only reflect 20% of the sun’s heat, the wall will help to keep the building and surrounding areas cooler when the sun bakes down on the city sidewalks, thus allowing the store to reduce its use of air conditioning in summer. Conversely, the plants will also act as natural insulation in winter, slowing down heat loss from the building and helping the company to draw on less power consumption.
Given all this, we are not going to say that the price stickers on Whole Foods’ luxury food items still won’t occasionally take your breath away, but with the plants doing their part, at least you will be breathing easier, not to mention more healthfully.
For more on green urban architecture see the following links:
National Geographic’s photo survey of urban rooftop gardens around the world.
The recent article on the Fairmont Waterfront Hotel’s rooftop apple trees in City Farmer News.