Versitank – Meadows Primary School, Melbourne

The need for innovative, energy-efficient ventilation systems in architectural design has never been more urgent or more important according to international air quality experts and epidemiologists. We now know that Covid 19 and many other viruses have aerosol transmission and to be protected, we need well ventilated spaces with measured low levels of CO2.

For this reason, we have revisited the major development 10 years ago of the Meadows Primary School in Melbourne’s North West, where a passive hydrothermal air conditioning system designed by NOWarchitecture provides excellent thermal comfort and air quality, while reducing energy costs by 50%.

The school was built on the world class, ground-coupled ventilation system using a series of Elmich, load-bearing Versitank recycled plastic, underground water tanks supplied by KHD Landscape Engineering Solutions. Within the foundation beams created by the sealed water tanks are ventilation pipes. The pipes carry fresh air drawn from outside and through the sub-floor. At 2 meters deep, the air is a constant 15 degrees Celsius year-round. The air tempered by the water enters the buildings through floor grilles, providing cooling in summer and raising the temperature of external air in winter. High ceilings allow the hot stale air to rise above activity spaces and exit through upper level louvered windows.

The underground tanks not only store recycled water that can be used for toilets and gardens but they don’t take up open space in the children’s playground.

An additional environmental benefit of using the load-bearing tanks was saving more than 300 cubic metres of concrete that would have been used on a more conventional project.

The physics of the system was checked at the time by CFD modelling and tested by FlowSim while the scale of the project garnered international attention.

NOWarchitecture’s Judith North and project architect Neville Cowland are proud of the design. Judith who believes ventilation in schools is a major problem said: “In the pandemic now, where there is high transmission of the virus, the Meadows Primary School has something very special and healthy.” Neville said at their last inspection the system was working well and providing a substantial amount of airflow. The only change he would possibly consider would be automating the opening and closing of the louvered windows as teachers are too busy to utilise the system as a learning experience for students.
The design though is very timely given the pandemic and environmental issues we now face.