Melbourne's Council House 2 (CH2) is an exemplar project, connoting "world leadership status" as the first building in Australia to earn a coveted 6 star Green Star rating.
Its inclusion of a range of sustainable design elements that work together in an “ecosystem” was at the vanguard of the mainstream green building movement.
The City of Melbourne faced a difficult decision in 2004. Its staff were housed in a range of buildings that were coming to the end of their natural lives.
In proposing a blueprint for their new home at CH2, they opted to go bold and sustainable.
“CH2 has been designed to not only conserve energy and water, but to improve the wellbeing of its occupants through the quality of the internal environment of the building,” the council said. “CH2 demonstrates a new approach to workplace design, creating a model for others to learn from and follow.”
CH2 has four operating modes: night, day, summer and winter.
Sustainable design features include wind cowls, chilled panels and beams, air displacement, “shower towers”, phase-change material, vaulted concrete ceilings, night purges, glare control, external timber shading and light shelves, heated water pipes, cogeneration, solar PV, and several others.
But a mere laundry list of these features ignores that they have been designed to work together, systematically.
Indoor environment quality and thermal comfort are optimised, but not at the expense of energy efficiency.
“CH2 has been designed to reflect the planet’s ecology, which is an immensely complex system of interrelated components,” the council says. “Just as it is impossible to assess the role of any part of this ecology without reference to the whole, CH2 comprises many parts that work together to heat, cool, power and water the building, creating a harmonious environment.”
Not all of the sustainable features work as was initially imagined. For instance, the distinctive yellow rooftop wind cowls are so heavy that the wind required to turn them occurs only rarely.
Overall, though, CH2 is a triumph of holistic design and an extraordinarily comfortable workplace. Many lessons learned from the project have been applied elsewhere.