People should “dream vertically”, said Sam Collins, general manager of Australian green wall designer and vertical installer.
Green walls, also known as vertical gardens, are regularly praised in the pages of architecture and design journals. But they are also increasingly on the “must have” list for new corporate builds because of their sustainability and welfare credentials.
Those massive vertical walls we often find in office spaces represent a lot of dead space, and vertical gardens are a way to decorate that space and effectively “reduce the urban heat island effect,” says Collins.
Thanks to nearly 60 completed vertical installations, 120,000 additional plants hang on walls around Australia. Projects range from a nine square meter vertical garden on the balcony of Universal Music in Sydney to a stunning conservation moss and leaf green wall in the reception area of Manunda Place, Darwin’s newest commercial hub.
“I love what we’re doing … bringing more plants into the world,” says Collins, whose company is benefiting from a surge in interest in a building solution that can help cool spaces, reduce diurnal temperature fluctuations and improve air quality.
Vertical has received grants from councils who want to see more green in their CBDs, but generally governments are still “dragging their heels”, says Collins.
“Governments need to step up and invest in green infrastructure,” he says.
Vertical gardens have four main benefits:
- Humans are instinctively drawn to living things; Well-being improves in the presence of nature
- Vegetation significantly improves thermal efficiency, which is why it makes sense to engage a green wall specialist early in the design process, says Collins. But vertical gardens can also be retro-fitted
- Vertical green walls, especially those fitted internally, absorb sound. The company achieved some excellent acoustic results for Sydney’s Woollahra Council after installing a large and complex green wall display at the local public library.
- Green walls create an oxygen-rich environment that significantly improves indoor air quality.
A new market has opened up in Perth for the Sydney-based company, but Western Australia’s hot and dry summers are testing the limits of what plants can survive on external walls.
The company taps into local sources of expertise, including a wholesale nursery supplier in Perth, to test which plants can survive Perth’s extreme heat.
Working in such harsh climates is an expensive process. “Sometimes we have to tell clients that we don’t know why certain plants failed,” says Collins.
Despite such risks, the company can provide a “permanent plant warranty with all risk on us”.
The company has 10 full-time and three part-time employees, including three qualified horticulturists.
Sustainability underpins everything they do. Plants are replaced every four years, and those removed end up in compost. Plants are kept in pots made of recycled plastic that can be reused multiple times and ultimately recycled again. Vertical also wants to increase the biodiversity of the project, including a focus on native species.
Ironically, internal green walls require higher maintenance than external walls, they benefit from nutrients blown onto plants or carried by birds and bees, and the wind can blow away dust or harmful insects.
Fire regulations pose a constant challenge for green walls due to concerns about the flammability of dried vegetation.
The vertical green walls have fully automated irrigation systems. But “we manage the risk of certifiers in a building,” says Collins.
Another challenge is that the gardens are maintained by the builders of a project for 12 months after completion but the maintenance goes to a strata body or a body corporate which is reluctant to pay the maintenance cost. To counter this, the company now offers 10-year maintenance plans for its installations.
“It’s not set and forget,” says Collins.