Cardinia Shire Council Civic Centre sustainable design features

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1 Cardinia Shire Council Civic Centre sustainable design features In late 2014, Cardinia Shire Council moved into its new civic centre at 20 Siding Avenue in Officer. The facility is rated five stars out of six under the Green Star rating tool for its design. Five stars represents Australian excellence in terms of sustainable design. Green Star considerations include management, energy, indoor environmental quality, transport, water, and construction materials. The initiatives incorporated in the building that contributed to its five star rating are summarised below. These features not only reduce the site s environmental impacts and operational utility costs, they also improve staff health and productivity. Figure 1. Sustainable timber at the front counter of the new civic centre. Management In the early stages of project development, a sustainable design consultant certified by the Green Building Council of Australia was engaged to assist with the sustainable design aspects of the building. This ensured sustainability considerations formed a core part of the building s design and were not added after the majority of the design work had been completed. A sophisticated Building and Energy Management System has been installed in the building. The system monitors and manages the operation of plant and equipment, controls the natural ventilation systems and monitors the site s energy consumption. The system allows for review of the site s energy performance and ongoing optimisation. The building has been designed to operate at 4.5 stars for energy efficiency under the National Australian Built Environment Rating System (NABERS) and initial analysis indicates that the building is tracking well in relation to this target. Construction waste was carefully managed through the building s development; 80 per cent of construction waste was reused or recycled. Cardinia Shire Council Civic centre sustainable design features 1

2 Figure 2. Building Management System energy monitoring. Energy The building fabric is of sufficient quality and supports energy efficiency through its insulating properties. Double-glazed windows are used throughout the facility. Shading has been positioned on external windows to protect them from the summer sun while enabling winter sun to provide heat to the building. The chillers and boilers that provide cold and hot thermal energy to the building are highly efficient. Figure 3. The civic centre from the north-west showing protective window shading. The building heating, ventilation and air-conditioning system is designed to minimise the use of mechanical equipment. If outside conditions are ideal for achieving desired indoor temperatures, the mechanical systems will switch off and windows will automatically open to provide natural ventilation. If outside wind speed is too high but temperature is suitable, the windows will not open as the wind speed will create an internal disturbance, but unconditioned air will be provided by the air handling units. Cardinia Shire Council Civic centre sustainable design features 2

3 The building incorporates variable air volume (VAV) capabilities. VAV is much more efficient than traditional constant air volume (CAV) systems. Air handlers for the building are located on the roof and under the building. These air handlers push the required amount of air into the building to maintain the required indoor air temperature. They extract thermal energy from the chilled or heated water and supply this to the building. If the building is close to the desired temperature the fans and associated thermal energy transfer run at a very low volume. If the building is moving away from the desired temperature, the fan speed is increased. This ensures only the required energy is used to maintain appropriate indoor environmental conditions. The building contains a significant amount of exposed concrete, providing thermal mass which stabilises internal temperatures; for example, in summer it absorbs heat during the day to assist with cooling the building. The building also incorporates a night purge system; during summer the building opens at night to purge heat from the day and absorb cool energy to assist with daytime cooling requirements. Figure 4. A work area within the building incorporating exposed concrete for thermal mass. The building incorporates a peak load lopping generator that can reduce the buildings peak electricity demand by over 20% to save on energy demand charges. This is more efficient than using electricity from the network produced by burning coal and saves on network transmission losses. This generator can also provide support to the electricity network at times of peak network electricity demand. The building incorporates an additional standby gas generator that can support its electricity requirements when electricity is not available from the network. Using gas for this purpose is more efficient that relying on diesel. Domestic hot water is heated as required by efficient instantaneous hot water units. Efficient lighting is heavily supported by natural light and light usage is controlled by motion sensors in meeting rooms (lights are only operational when rooms are occupied) and timers for the general office area. Office perimeter lighting is controlled by a daylight harvesting system, so it dims and reduces energy consumption when natural light is avalible. Activity-based working is practiced in the office; individual staff do not have a permanent desk but are free to move around the building to use a range of spaces when working from the office. This Cardinia Shire Council Civic centre sustainable design features 3

4 work style reduced the floor space and the number of desks required as not all staff need a dedicated desk all day. This also reduces the number of areas that need to be lit, reducing lighting energy requirments. All staff use energy efficient laptop computers. Indoor environmental quality Volatile organic compounds (VOCs) are chemicals emitted from materials that have negative impacts on human health. Glues and paints often contain these substances. To improve the quaility of the indoor environment at the civic centre, materials with low VOC content were selected including paints and carpet tiles. The building design includes atriums and windows that provide a high level of natural light which has proven health and productivity benefits. Surfaces have been designed to reflect light through the facility and light shelves on north-facing windows assist with reflecting light into the office space. The building is designed to provide a thermally comfortable space for occupants. Air is delivered to the office floors through evenly distributed floor vents from a floor cavity. This reduces the required air volume from each point of diffusion and improves the distribution of air, assisting with occupant comfort. The building provides access to outside views and has a low background noise level, further contributing to a high level of indoor environmental quality for occupants. Figure 5. Natural light entering the building through the atrium. Cardinia Shire Council Civic centre sustainable design features 4

5 Figure 6. Diagram demonstrating building s sustainable design features. Cardinia Shire Council Civic centre sustainable design features 5

6 Transport The building is located close to the Officer train station, making it convenient for staff and visitors to commute via public transport. Electricity outlets have been made available in the civic centre s car parking area for electric car charging. Significant cyclist facilities are available, including a bike storage area, change rooms, showers and lockers for cyclists. These features make it easier for staff to travel to work using sustainable methods. Water The site contains a 20,000-litre rainwater tank located underneath the car park. Rainwater is captured from the building and reused for toilet flushing and irrigation as required. When the rainwater tank is empty during dry periods, recycled water is used for these purposes. Recycled water requires energy to filter, clean and pump, so the preference is to use rain water when available. Water-efficient taps and fixtures are used throughout the building to minimise water usage and waterless urinals have been installed in the men s bathrooms. A recirculation system has been installed for the fire water system. Requirements to flush and test fire water systems regularly have traditionally been completed by flushing water out of the systems to the sewer and re-pressurising them, leading to water wastage. This building recaptures water from the system into a fire water test tank to avoid this wastage. The water from the tank is reused in the fire water system. Construction materials Almost all (95%) of the timber used in the development of the building was either reused or certified as a sustainably sourced timber. Concrete used for the build contained recycled content in greater than standard practice levels and the use of toxic materials such as PVC was greatly reduced in the building. Processes were put in place to ensure that steel used was locally sourced and produced using energy efficient processes. More information For more information on this project, please contact Cardinia Shire Council s environment officer on or mail@cardinia.vic.gov.au Cardinia Shire Council Civic centre sustainable design features 6