Green Walls for Greener Cities
Contact with nature is not just an amenity: it's important for well-being. Green walls liven up urban spaces while improving building performance.
I live in Vermont, where agriculture is an integral part of our culture. I drive past the farms as the seasons change and see when the corn is high or when too much rain has made plowing impossible. And the family sees the results at the local farmer's market. Whenever I visit urban areas, I inevitably end up at the local park or waterfront for my early-morning runs.
I value this connection with the natural world--or biophilia--and maybe it's more than just a lifestyle choice. Biophilia has been shown to have tangible benefits, including reduced stress, improved productivity, and faster healing, to name a few, but integrating greenery among limited--and expensive--urban real estate is no easy task. Maybe the answer is to think vertically.
What is a green wall?
Exterior green walls, sometimes referred to as living walls, green facades, eco-walls, and a variety of other names, use frames mounted to exterior walls to support vegetation growth. Their greenery helps
- break up the urban landscape of concrete, glass, and steel;
- improve the thermal performance of a building by creating shade and an air space between the plants and the building;
- absorb carbon dioxide;
- mitigate stormwater runoff;
- and reduce heat and noise.
And since thermal performance and energy-saving design are not visible to the public, green walls are one way for building owners to advertise their green credentials.
GSky exterior Pro Wall System
But green walls have to be well designed and maintained or else you can end up with mold, moisture damage, or dead plants. GSky's exterior Pro Wall System reduces these risks using a stainless steel frame and panels that incorporate a structural growth medium. The plants are pre-grown to design specifications, monitored for temperature and moisture, and watered automatically using a drip irrigation system.
Designing the wall is no easy task. It begins with careful assessment of the site, water and drainage consideration, seismic and wind loads, and power and placement of the irrigation system. Local plants are then selected and pre-grown in a nursery before the panels are installed along with the frame, irrigation, and monitoring system.
The monitoring system is automated, setting off alerts if there is a problem with the irrigation, and can be paired with GSky's maintenance program. These green walls do not have to be a single shade of green, either. Using different plant species, you can create designs within the greenery.
More basic green walls
GSky also offers its Basic Wall Container System, which contains a trellis and integrated containers to support vine growth. The containers are three feet and five feet high, and the vines can be either pre-grown or allowed to grow naturally, which could take up to two years.
You can't get plant designs with these systems. They are meant for large exterior walls, and can even include a catwalk behind the façade of plants for easier maintenance on high walls. Like the Pro Wall System, they come with an irrigation and monitoring system.
Keeping the "green" in "green wall"
Providing the benefits of biophilia using a green wall only works if the plants are actually green. GSky ensures its systems perform with warranties of ten years on the planters, five years on the irrigation system, and a "100% Plant Health Guarantee" when paired with the maintenance contract.
We've updated our green walls section in GreenSpec and added a couple of new products. Check them out. While green walls might not be ideal for every building or climate, the more greenery we can add to urban environments, the more I'll feel at home while visiting.
Posted by Brent Ehrlich on January 25, 2012
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