St. Justins School – Oran Park

Project Name: St Justins School
Location:
Oran Park, NSW
Client:
Catholic Education office (CEO)
Architects:
Thomson Adsett
Engineers:
Medland Metropolis
Project Cost:
$8 million approx.

Project Brief

The Catholic Education Office commissioned Thomson Adsett to design a new sustainable school at Camden. Vim Sustainability was appointed the sustainability consultants on the project in 2010.

The location of this facility in the outer western suburbs of Sydney has a stark contrast in climate throughout the year, being very hot in summer and very cold in winter. The high diurnal range provides good opportunities for night purging, using natural ventilation to improve building cooling and reduced air conditioning costs.

Vim Sustainability provided a range of ESD strategies around natural ventilation and daylighting, internal comfort and detailed thermal/energy modelling.

Local Climate Analysis

The first step in our strategy for this project was to undertake a local climate analysis that assisted us in compiling the most effective sustainable design strategy around building typology and material/fabric configuration which was then used by the Architect.

Daylight Software Modelling

Using ‘Radiance’ software we were able to identify the efficacy of a range of daylighting options that utilised current window configurations and the option of SUNPIPE® natural daylighting systems. Vim then made a range of recommendations to improve daylight access by changing the configuration and layout of the glazing. We also made recommendations on the use and location of SUNPIPES in the facility.

This process enabled us to select the best glazing /daylighting option and make those recommendations to the client.

Natural Ventilation Diagnosis

We then undertook a natural ventilation diagnosis utilising the shape of the building and window opening sizes and layouts to identify the best ways to bring air into and out of the building through pressure differences. Different wall shapes were created or added to the façade to provide the pressure differences that could accelerate the air flow into and out of a room via the glazing resulting in a maximised energy free natural ventilation option.

CFD Modelling

We also looked at the efficacy of the stack effect of utilizing high level windows as part of the natural ventilation regime. Once we had reconfigured the façade to improve the air flows we then undertook CFD modelling to validate our air flow regime but also to identify the freshness of air through the building using Green Star ‘Air Change Effectiveness’ criteria in our CFD and Thermal modelling software.

From the CFD analysis we are also able to identify the air temperatures inside the classrooms across some agreed time frames.

Thermal Modelling and Comfort Protocols.

In addition we also undertook detailed thermal modelling based around the adaptive comfort standard protocols and highlighted to the client the months of the year when the internal temperatures would be under 28⁰C and above 20⁰C.

This helped the client understand the thermal impact of building typology decisions and also the amount of time the inhabitants would be inside or outside an agreed comfort level across the year. The information was also used by the client to understand how much supplementary heating and cooling would be required inside a predefined comfort range across the year, before the building design was finalised.  Recommendations were then made by us as to the best value options to maximise efficiency in the fabric design within cost constraints and buildability issues.

Final Design Strategy & Recommendation

Finally we provided a detailed design guide spreadsheet that highlighted all the ESD Initiatives considered in the project – regardless of whether they were accepted or rejected during the design process. This sheet was updated as the job progressed, which enabled options to be considered based on their cost, value, risk and opportunity as well as efficacy. This format allows the client easy access to the information and the ability to understand the concepts suggested and why they have been accepted or not using layman’s terms and explanations.