Sustainable – by design
Colleagues at a Melbourne architectural firm are achieving excellent outcomes in sustainable building design, with a specific focus on early childcare development projects and primary and secondary educational facilities. DENIS SWEETNAM and HAL CUTTING from Baldasso Cortese Architects explain the value of collaborating with clients.
Thirty percent of Australia’s carbon emissions come from buildings. This figure increases to 40 percent when one includes the construction of these buildings. This is equivalent to carbon emissions from all the cars and trucks in Australia on the road at any one time.
By reducing our energy consumption with a subsequent cost saving and by making our buildings healthier, we are improving the Earth’s environment, our own lives and the lives of future generations – and all we need to do is design buildings to operate more efficiently.
While they have becoming increasingly important, particular ESD (environmentally sustainable design) elements have only been mandatory in building design in Australia since May 2006. Since that time buildings lodged with councils for permit approval must comply with the energy efficiency requirements set out in Section J of the Building Code of Australia (BCA).
Section J lists objectives, functional statements and performance requirements for energy efficiency provisions. It specifies the exact intent of the new measures, namely to reduce greenhouse gas (GHG) emissions by efficiently using energy.
Section J requires best performance for the following elements of a proposed building:
1. building fabric
2. external glazing
3. building sealing
4. air movement
5. air-conditioning and ventilation systems
6. artificial lighting and power
7. hot water supply, and
8. access for maintenance.
In the field of childcare/education facilities the consideration of ESD principles is essential. Thermal mass, which stabilises the indoor environment, solar hot water, natural ventilation and night purging, rain water harvesting, daylighting and green roofs are just some of the elements we have been incorporating into our recent designs
Well-designed facilities that incorporate ESD initiatives will enjoy recurrent cost savings and a reduction in greenhouse gasses over future years. Educationalists, local councils and the wider community want ESD incorporated into their schools and childcare centres, and many are now embracing it.
ESD has previously been seen as an add-on rather than an integral part of the building design, and it used to be the first thing deleted from the budget. We are, however, now able to quantify costs – both capital and life cycle – to demonstrate the cost benefits over the life of educational and community facilities.
Denis Sweetnam is currently designing an environmentally sustainable children’s hub on an existing primary school site in Victoria under an integrated management structure, including long day childcare, kindergarten, occasional childcare, out-of-school hours care, family play groups, maternal and child health services, allied health services and community meeting facilities and toy library.
A green roof is one of the innovative elements of the design. There are many benefits to the green roof, including thermal and acoustic performance.
The roof will also assist with rainwater management, solar control from hot western radiation and protection from damaging coastal winds. It will also provide an additional area where children can play and families gather. It will become a significant and visible ‘green’ statement for the council. All the ESD elements are considered by the shire council to provide an educative experience not only for the children using the building, but also for the parents and the wider community.
Water harvesting and management is likely to be more regulated in the near future.
There are many benefits to water management, especially in Australia. We encourage clients who are interested in creating sustainable environments to include significant water management initiatives. Some of the benefits of rainwater harvesting include:
* free water for toilet flushing and landscape irrigation
* reduced mains water usage – this is significant as the cost of water will increase over time, and
* reduction in run-off through alternatives to asphalt and concrete pavements.
Common volatile organic compounds (VOCs) are key factors in indoor air quality issues, such as sick building syndrome – generated by photocopiers, carpets and furnishings, as components oxidise, or through contact during use. One irritant, formaldehyde, is present in hundreds of office components, including wood and laminated furniture, shelving and wall covers. It is of considerable concern in the design of schools and childcare facilities.
Creating carbon-neutral VOC emissions over the long-term will create considerably healthier and safer places to work and play.
Strategies currently under consideration for the proposed children’s hub to ensure good indoor air quality are:
* avoidance of building materials containing VOCs
* avoidance of excessive fitout materials that collect dust
* regular replacement of indoor air with outdoor air through natural ventilation strategies when the external climate is favourable, and a ventilation strategy that uses geothermal air tempering when the untempered outdoor air is unsuitable
* indoor plants that actively improve the environment – this can be achieved with normal pot plants, vertical plant walls or bio-filtration walls, and
q use of interior paint that actively degrades indoor air pollutants.
Other ESD strategies for reducing energy consumption for the proposed children’s hub include:
* reverse block veneer construction (i.e. with thermal mass on the inside and insulation on the outside)
* solar hot water panels
* daylighting to reduce the need for artificial light
* sun control to reduce solar radiation
* hydronic heating integrated into the building fabric, and
* green roof design.
We’ve also reduced the reliance on air-conditioning with designs allowing fresh air reticulation within the slab and ‘heat chimneys’ to aid the circulation of air. Studies have shown that student attendance and results have improved significantly in schools designed to incorporate fresh air reticulation.
Natural ventilation in the learning spaces and the managing of the internal temperature in schools through proper orientation, wide eaves, insulation and reducing western sun exposure, will dramatically reduce long-term running costs and provide a healthier environment than reliance on air-conditioning.
With increased environmental awareness, there is no doubt that ESD principles are paramount in the design process of building projects. Baldasso Cortese believes every project now requires a vigorous ESD ‘workshop’ with the client at its commencement to ensure concepts are understood and to flesh out those ESD initiatives that will minimise energy consumption and building life cycle costs, while achieving the lowest environmental impact possible.
Denis Sweetnam is a senior manager at Baldasso Cortese Architects. His expertise is in the innovative design of childcare facilities. He authored the current Design Guide for Victorian Children’s Services for the appropriate design of childcare centres.
Hal Cutting is a partner at Baldasso Cortese Architects. His experience lies in the master planning and design of education facilities. With an extensive understanding of curriculum and pedagogy, Hal creates functional facilities that stimulate both students and teachers to grow in a sustainable environment.