People should “dream vertical”, quips Sam Collins, general manager of Australian green wall designer and installer Vertikal.
Green walls, or vertical gardens as they are also known, are regularly lauded in the pages of architectural and design journals. But they are also increasingly on the “must have” list for new corporate builds because of their sustainability and wellbeing credentials.
Those huge vertical walls we often find in office spaces represent a lot of dead space, says Collins, and vertical gardens are a way to decorate that space and effectively “lower the urban heat island effect”.
There are an extra 120,000 plants hanging from walls around Australia thanks to about 60 installations completed by Vertikal. The projects span from boutique installations such as a nine-square metre vertical garden on the balcony of Universal Music in Sydney, to a stunning preserved moss and foliage green wall in the reception area of Darwin’s newest commercial precinct, Manunda Place.
“I love what we do … bringing more plants into the world,” says Collins, whose company is benefitting from an upsurge in interest in a building solution that can help cool spaces, reduce daytime temperature fluctuations, and improve air quality.
Vertikal has received grants from councils who want to see more greenery in their CBDs but Collins says governments in general are still “dragging their heels”.
“Governments should push for this and invest in green infrastructure,” he says.
There are four key benefits to vertical gardens:
- Humans are instinctively drawn to living things; wellbeing improves in the presence of nature
- Vegetation significantly improves thermal efficiencies, 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 fantastic acoustic results for Sydney’s Woollahra Council after installing a large, complicated green wall display in the local public library
- Green walls create an oxygen-rich environment that significantly improves internal air quality.
A new market has opened up in Perth for the Sydney-based company but Western Australia’s hot, dry summers are testing the limits for plants that can survive on external walls.
The company is tapping into local sources of expertise, including a Perth wholesale nursery supplier, to test which plants can survive Perth’s extreme heat.
Working in such extreme climates can be an expensive process. “We sometimes have to tell clients we don’t know why certain plants failed,” Collins says.
Despite those risks, the company can provide “a constant plant warranty where all the risk is on us”.
The company is staffed by 10 full-time and three part-time employees, including three qualified horticulturists.
Sustainability underlines everything they do. Plants are replaced every four years and those removed end up in compost. Plants are housed in pots made of recycled plastic that can be reused multiple times and are ultimately recycled again. Vertikal also wants to increase the bio-diversity of its projects, including focussing on native species.
Ironically, internal green walls require higher maintenance than outside walls that benefit from nutrients blown onto the plants or carried in by birds and bees, and where wind can clear away dust or harmful insects.
Fire regulations present an ongoing challenge for green walls because of concerns about the combustibility of vegetation that has dried out.
Vertikal’s green walls have fully automated watering systems. But “day in, day out we are dealing with certifiers’ risk on a building”, Collins says.
Another challenge is that the gardens are maintained by a project’s builders for 12 months after completion but then the maintenance passes on to a strata body or a body corporate that may be reluctant to pay the maintenance costs. To counteract this, the company now offers 10-year maintenance plans for its installations.
“It’s not set and forget,” says Collins.