Case study: Canberra’s first Green Star multi-residential project
Willow Aliento | 16 December 2014
Located within Canberra’s Constitution Avenue urban renewal precinct, the mixed-use Jamieson Apartments project – developed by Anglican Diocese of Canberra and Goulburn, designed by Cox Architects and constructed by Hindmarsh Construction – is the ACT’s first Green Star multi-residential project.
Being a first, there was a considerable education task required to ensure the project team were up to speed, according to Amir Girgis, Northrop Consulting Engineers sustainability manager Sydney.
Northrop was appointed as the project’s sustainability advisors in 2009, and later took on the role of Green Star consultant. The project has a 4 Star Green Star Design rating under the Multi-Residential tool v1, and Girgis says it is “on track” to achieve 4 Star Green Star As Built too.
A broad range of environmental initiatives were incorporated into the design, including energy-efficient and water-efficient plant and fixtures; rainwater reuse to reduce potable water consumption; sustainable building materials; and passive design elements to maximise thermal comfort.
A lifecycle approach was taken to ensure the sustainability aspects deliver long-term benefit for residents through reduced water and energy costs, an improved indoor environment with natural ventilation, extensive daylighting, and minimised use of products containing volatile organic compounds or formaldehyde. Products and materials were selected that have a reduced impact on the environment and reduce the amount of natural resources consumed in their make and manufacture.
The aim was also to reduce the building’s operational environmental footprint overall, so residents are making a smaller ongoing contribution to greenhouse gas emissions.
Northrop sustainability engineer Bridgett Glasson said the Green Star rating future proofed the asset value, with evidence emerging that a rating translates into higher sell-on prices.
The project is located in an area of identified heritage, and neighbours St John’s Church. This imposed a requirement that the design and materials had to be sympathetic to the Church’s aesthetic and link with the existing building on the site, an office for the Anglican Diocese of Canberra and Goulburn, which was to be demolished. This gave the team an opportunity to gain Green Star points under the Innovation Challenge through demonstrating the heritage value and historical aspects of the project.
Mr Girgis said recycling of both demolition waste and construction waste was prioritised, and that construction activities were managed to minimise pollution and protect soil and water quality.
“Jamieson Apartments was the first multi-unit residential building in the ACT to be awarded a Green Star rating. While being first carries status rewards it meant we had to innovate,” he said.
“The lack of industry experience in delivering Green Star residential buildings was a sticking point. While it was true that many contractors had experience working with Green Star, they had all been office projects. The shift required was not a subtle one, so we found ourselves at first pioneering and then passing on that knowledge – effectively acting in the role of educators for contractors working on the project.
“This project’s Energy Efficiency Rating was a particular challenge – our target was a 7.5 star ENE rating, significantly above the required six stars. As any engineer in property will tell you, energy plays a significant role in achieving a good Green Star rating.”
Key initiatives in achieving energy efficiency included:
- Optimised façade design and passive design elements to achieve an average NatHERS rating of 7.5 Stars
- High energy rated appliances, and energy efficient fixtures and fittings to reduce energy consumption by around 30 per cent
- Energy efficient airconditioning and lighting design, including a dwelling shutdown switch located at the entry to turn off all AC and lighting in the apartment when unoccupied
The project also has a number of water-saving aspects including installation of high-rated WELS fixtures and fittings that reduce water use by about 10 per cent, and a rainwater harvesting and re-use system that reticulates the rainwater for toilet flushing and irrigation.
Waste and recycling facilities have been incorporated into the project that will make it easier for residents to divert waste from landfill, and sustainable transport is also being encouraged with bike storage for every apartment. The development is also within easy reach of public transport.
Mr Girgis said that of all the project’s challenges, the biggest was one “to which there was no simple and elegant engineering solution – time”.
“The project had taken a nine-month break part way through development. During that hiatus, the sustainability goals of the project had received a bump upwards,” he said.
“While admirable, that shift in focus also required redesigns and the application of new sustainability techniques and hardware.
“The extended development period also brought significant challenges in continuity – the longer the project, the more contractor churn you’ll experience. That added to our workload as contractor educators.
“Unfortunately, there is no single fix for an extended project – it just required that we devote lots of time to communication, both with the client team and contractors, which certainly helped the project run more smoothly.”