When Mirvac first began developing the Yarra’s Edge precinct in Melbourne, the language of green building was still a work in progress. The same can be said for the sustainability initiatives incorporated into the plans, which themselves have evolved as each stage has unfolded.

Due to be completed in 2015, the final stage of the project, Wharfs Entrance, takes it up another notch, with plans incorporating aspects of the sharing economy as well as energy-efficiency, water-efficiency and some innovative public open space elements.

This stage comprises Forge, a 30 level tower with 228 apartments; Cargo Homes, constituting seven home offices; the 11 riverside detached homes of Wharfside Residences; and new public amenities including a pool, gym, cafe, park and native garden.

The previous stages have seen Mirvac complete seven towers with a combined 1162 apartments and 82 strata-free homes, with about 2500 people now living in the Yarra’s Edge community.

Paul Edwards

Paul Edwards, Mirvac’s group general manager of sustainability, says that when Mirvac first started masterplanning 15 years ago, a Design Environmental Management Plan was mapped out for the entire precinct, and good environmental practices put in place for the firm’s entire commercial and residential portfolios. The Yarra’s Edge plan was audited regularly to ensure developments were adopting and improving on sustainability.

Edwards says the company’s DEMP for the precinct evolved into the broader Docklands ESD guide, making sure there was a level playing field set up for all the developers active in Docklands in terms of ESD benchmarks.

“As we’ve grown and learned, we’ve added to it,” Edwards says.

The industry has shifted further into the green since work began, with tools such as Green Star for multi-residential buildings now available, and a wider range of energy-efficient and sustainable products, materials and systems available. Design itself has also adopted some basic principles that have in turn become part of the Building Code, such as requirements for ventilation, passive thermal measures around orientation and thermal performance of the building envelope.

“So on projects today, we combine all of those things – the orientation of apartments, and a building by building standard for appliances and choice of products,” Edwards says.

Apartment sustainability

The apartments are designed to an average NatHERS rating of six stars, with specific energy efficiency measures varying across the different stages and dwelling types. Standard across all of them is what Edwards calls a “green switch” – also known as a “kill switch” – by the front door, which enables people to turn off all non-essential appliances and systems when they leave the dwelling. Double glazing has also been standard across all dwellings.

The detached homes of each stage have solar pool heating and solar hot water services, and one of the towers also has solar panels used to supply power for common areas. Not all the towers have them, though, as Edwards says the small roof area combined with orientation and location makes some buildings poor candidates.

The Forge tower does, however, have a rainwater storage tank that will be reticulated for toilet flushing. Low-e coated double glazing is being used to reduce the thermal impact from solar gain, and solar exposure has been reduced on the western facade. Hot water is being provided via a gas-fired ring main, and a centralised water condenser loop system is being used for cooling.

All the apartments have private outdoor areas, balconies on lower levels and wintergardens at higher levels to reduce the impacts of wind within the space.

End of trip facilities are being provided in a common space and are for visitors as well as residents, and there is bicycle parking also for both residents and guests. Yarra’s Edge has a cycle path that connects it to the CBD.

One of the key elements of this part of the precinct is the public space. The pool has a grassed roof that curves up and over the pool, extending the open public space. To increase garden area, a pontoon will be constructed that will host a floating native garden called “Where We Belong”, watered by stored rainwater, with pumps for the irrigation powered by solar panels along the sides of the pontoon. Edwards says the idea is the garden is self-sustaining, and brings back an element of the original ecology of the area including orchids and native grasses.

“We have a commitment to bringing nature to Wharf’s Entrance,” Edwards says.

“We are also using recycled wharf materials throughout to demonstrate our commitment to materiality. It’s these little things that make a difference.”

Throughout all the stages, low-VOC paints have been used in interiors, and LED lighting has become standard.

Minimising construction waste has also been made a priority, with a 95 per cent recycling rate targeted. Currently 92 per cent is being achieved, but Edwards says the ultimate target is zero waste to landfill.

Circular economy spaces

At Forge, there is also the possibility of communal herb gardens being constructed, and the project is likely to include spaces for swapping books in the common areas and a large item storage space, so there are spaces for the circular economy to operate.

“This will all link into an app,” Mr Edwards said.

The idea came from monitoring how public spaces have been used in previous projects, where it was observed that people engage around book swapping. Edwards says the goal is to implement initiatives that are not over-complicated in their management.

He says the company’s sustainability strategy released last year, “This changes everything”, sums up what the company is about and what it is trying to achieve.

One of the commitments in the strategy was to educate a million people about sustainability. Yarra’s Edge will make a contribution to that with a digital building user’s guide for owners that explains how to use features like the green switch and where recycling facilities are located, and will also routinely deliver tips on energy and water efficiency, and living a sustainable lifestyle.

“Given where we see energy, water and waste bills going, it’s important to look at building running costs,” Edwards says.

“You can do fantastic [high technology] solutions, but they can cost a lot ongoing. We’d rather take a pragmatic and practical approach. We make sure the products we’ve got are suitable solutions.”

Prefabricated bathrooms

Prefabrication is also being used at Yarra’s Edge, with the company deciding 14 months ago to start using modular bathrooms constructed offsite.

“There is less waste [with the modular bathrooms], energy can be monitored and managed during fabrication and there is an opportunity to reduce overall transport-related carbon emissions, improve workplace health and safety and improve quality,” Edwards says, adding that the firm is taking one step at a time towards increasing its use of modular construction elements.

“We are currently reviewing all opportunities with regards to modular; not all our projects will be suitable for it. And we will also be improving our understanding of the benefits of modular construction.”

One of the strategies the company has used to refine designs and decide on sustainability initiatives has been to engage with current and potential customers to find out what they want: is it composting? Electric cars? More recycling?

Consultation

Mirvac will be engaging in consultation over the next few months to “find out what people want, what their pain points are, and how we can raise our standards further”, Edwards says.

“We are always looking at opportunities to improve the efficiency of our product, and having our own big design department is a huge benefit for us.

“We have an integrated model, so there are cross-sectoral learnings between the commercial office division and the residential division.

“We also have asset owner and manager lifecycle assessments being rolled out across our different projects to give us insights into materials, and to identify the hot spots in our supply chain so we can reduce the embodied footprint of our buildings.”