10 Key Principles of Environmentally Sustainable Design: Enhancing Building Performance and Comfort
In the escalating pursuit to create a world that respects our environment, applying environmentally sustainable design (ESD) principles to new developments is crucial. These principles extend beyond simply 'going green.' They encompass a broad range of ten categories that collectively contribute to reducing negative environmental impacts and improving the health and comfort of building occupants. This blog post provides a comprehensive analysis of these ten categories: indoor environment quality, energy efficiency, water efficiency, stormwater management, building materials, transport, waste management, urban ecology, innovation, and construction and building management.
Environmentally Sustainable Design (ESD) tools serve as a robust measure for evaluating the design or actual performance of a proposed building. They establish benchmarks that enable the comparison of a building's performance with similar types of structures. These benchmarks typically offer immediate and dependable insights into numerous parameters such as energy consumption, greenhouse gas emissions, savings in potable water, stormwater treatment, embodied energy emissions, as well as daylight and ventilation.
For the majority of instances, they are a reliable source of performance indicators.
Although ESD tools aren't typically mandated, there are certain exceptions. For instance, the NatHERS tools are often utilized to demonstrate compliance with energy standards specified in Part 3.12 of Volume 2 of the National Construction Code (NCC).
This applies to single residential houses as well as multi-residential housing. Similarly, the NABERS tool is enacted via the Commercial Building Mandatory Disclosure Scheme. This scheme mandates that any commercial office space of 2000m2 or larger that's for sale or lease must disclose its operational energy performance. However, other ESD tools are generally not required within Australia, and are often used on a voluntary basis. In 2003, the Green Building Council Australia launched their first Green Star rating tool, which has since been instrumental in transforming the higher tiers of the commercial building sector through its rating scheme.
Indoor Environment Quality
Enhancing the quality of the indoor environment, both at home and in the workplace, is directly linked to improving well-being and reducing the risk of health issues. By adopting passive design principles, superior indoor environment quality can also result in significant energy savings as a result of lessened energy requirements for heating, cooling, and artificial lighting. This segment recommends strategies for elevating indoor environmental qualities by making informed decisions about building design and the selection of products and materials.
On average, Australians allocate almost 90 percent of their time to indoor activities. Given the substantial impact that indoor environments can have on our mental and physical health, it is crucial to secure good indoor environment quality in both our residences and workplaces. Astoundingly, the Commonwealth Scientific and Industrial Research Organisation (CSIRO) estimates the price of substandard indoor air quality in Australia to be potentially as steep as $12 billion annually, resulting from compromised health and productivity losses.
Main Factors Defining Indoor Environment Quality
The quality of an indoor environment is determined by several key factors, each playing a substantial role in our overall well-being and productivity levels. Let's delve deeper into these factors:
1. Light: Adequate lighting is crucial for visibility, mood, and even biological rhythm regulation. Natural light, particularly, has a beneficial effect on mental health and productivity. Buildings designed to maximize daylight exposure can significantly enhance the indoor environment.
2. Views: Access to outside views, especially those of natural elements, can lower stress levels and improve mood. Provision of clear and unobstructed views from a building should be a major consideration in sustainable design.
3. Air Quality: Indoor air quality has a direct impact on occupant health. Poor air quality may lead to a range of health issues like allergies, asthma, and respiratory infections. Minimizing the emission of volatile organic compounds and ensuring efficient air filtration can improve indoor air quality.
4. Ventilation: Proper ventilation is crucial for maintaining air quality by removing indoor pollutants and maintaining temperature and humidity levels. It provides fresh air, improves comfort, and reduces the risk of airborne infections.
5. Thermal Comfort: This refers to satisfaction with the thermal environment. It's vital to maintain an optimal indoor temperature through energy-efficient heating and cooling systems, ensuring comfort and aiding concentration.
6. Noise: Excessive noise can harm concentration, interfere with communication, and lead to increased stress levels. Buildings should be designed to minimize external noise, with adequate sound insulation.
7. Occupant Control: Allowing occupants to control their environment (like adjusting lighting and temperature) can enhance comfort, satisfaction, and productivity.
8. Materials: The choice of building materials can significantly affect indoor environment quality. Materials that emit low or no volatile organic compounds and allergens can improve air quality, while those with good thermal properties can enhance thermal comfort.
By holistically considering these factors during the design phase, we can create indoor spaces that are not only environmentally sustainable but also promote health, well-being, and productivity.
Energy Efficiency
Our buildings, both residential and commercial, account for approximately 40% of global energy consumption. In Victoria, around 70% of total greenhouse gas emissions are attributed to electricity use, largely due to the predominance of brown coal. By incorporating passive design principles such as thermal mass, external shading, optimal building orientation, cross ventilation, and superior insulation, we can decrease dependency on energy-intensive mechanical systems for maintaining indoor comfort. The adoption of renewable energy sources can further diminish a building's environmental footprint. Effective building design can curb energy use, thereby saving costs and mitigating the impacts of climate change. Conversely, poorly designed buildings can be costly and contribute to greenhouse gas emissions.
Both individual homeowners thinking about renovating their current dwelling and developers envisioning multi-storey constructions must prioritize environmentally sustainable design (ESD) right from the project's preliminary planning stages. It's important to note that integrating sustainable measures post-design completion tends to be a more expensive and complicated process. Hence, addressing ESD components early in the project lifecycle not only fosters a greener, more responsible building ethos but also proves to be economically sensible.
In a significant stride towards sustainability, the minimum energy requirement in the Nationwide House Energy Rating Scheme (NatHERS) has been recently revised from 6 to 7 stars. NatHERS, which assesses the thermal performance of Australian homes, has made this change in recognition of the dire need to reduce residential energy consumption and, in turn, mitigate the effects of climate change.
This transition to a higher energy rating standard will have considerable positive implications for homeowners and the planet alike. For homeowners, a 7-star rated home means significantly reduced energy bills. These homes are more thermally efficient, requiring less energy for heating and cooling, and thereby offering substantial savings in the long run. Additionally, such homes ensure enhanced indoor comfort, with optimal temperature maintained throughout the year, boosting the overall living experience.
The shift from 6 to 7 stars in the NatHERS rating system signals not just an evolution in Australian building standards, but a commitment to creating a more sustainable and energy-efficient residential landscape. It is a testament to the growing recognition of the role our homes play in addressing climate change and paves the way for a greener future.
Water Efficiency
Imagine a typical family of four in Melbourne. Each year, they consume approximately 240,000 litres of water, equivalent to filling 3000 bathtubs or covering 10% of an Olympic-size swimming pool. Surprisingly, a staggering 90% of this water is not for drinking but rather used for toilet flushing, gardening, and similar tasks that require potable water.
As our population continues to grow and the climate changes, it becomes increasingly urgent to reassess the accessibility of freshwater resources and devise strategies for their more efficient and mindful utilization. Let us recognize the importance of preserving and wisely managing this precious resource.
Efficient water usage yields a multitude of advantages. For starters, it helps lessen the expensive demand for infrastructure upgrades, such as desalination plants, and consequently reduces your water bills. It also future-proofs your property investment and guarantees a water supply that remains unaffected by water restrictions. Furthermore, it allows for maintaining your garden during periods of low rainfall and results in less sewage discharged into rivers and oceans.
In the wake of growing awareness regarding water security, properties designed for water efficiency are increasingly appreciated by both tenants and homebuyers. Hence, it's prudent to incorporate water-saving measures like water-efficient fittings and fixtures (like taps, shower heads, etc.) and rainwater tanks connected to toilets and irrigation systems from the get-go while renovating or constructing new buildings. Doing so helps avoid future retrofitting costs.
Stormwater Management
The relentless urban growth and sprawl in Melbourne have led to a significant surge in the extent of impermeable surfaces such as buildings, roads, and parking lots. This transformation means that rainfall in urban areas largely turns into runoff, or stormwater. Traditional methods of stormwater management redirect this water into urban tributaries, unintentionally transporting pollutants into our rivers and eventually, Port Phillip Bay. This rise in stormwater runoff doesn't only jeopardize the health and attractiveness of our waterways for humans, flora, and fauna, but it also escalates the risk of flooding, causing potential harm to both natural and man-made surroundings.
Water Sensitive Urban Design (WSUD) is a revolutionary approach that effectively captures, purifies, and recycles stormwater on-site, significantly enhancing the quality and volume of water flowing into our rivers and streams. Incorporating WSUD into your construction project helps mitigate its downstream effects and provides an opportunity to conserve drinking water by replacing it with harvested rainwater. The strategic implementation of WSUD can bring about numerous beneficial outcomes such as enhancing water quality in streams and groundwater, safeguarding stream and riparian habitats for local flora and fauna, preventing bank erosion along our waterways, reducing the risk of flooding, and protecting the aesthetic and recreational appeal of streams. Furthermore, it contributes towards potable water conservation by offering an alternative water source for applications like irrigation and toilet flushing.
Building Materials
The construction industry plays a significant role in consuming raw materials, accounting for approximately 30-50% of global extraction. With the building sector experiencing substantial growth, this demand is expected to increase, putting even more strain on our limited resources. Ongoing refurbishments, extensions, and fit-outs further contribute to the environmental impact of buildings throughout their lifecycle. Hence, it is crucial to consider the environmental consequences when making decisions about material sourcing. These impacts arise from various factors, including the extraction of raw materials, the high energy embodied in certain materials, recurring maintenance needs, and the challenges associated with recycling certain materials.
By making informed and deliberate choices regarding the materials used in construction and outfitting, we can achieve significant benefits. This includes assessing the feasibility of reusing existing materials, cost savings in construction, refurbishment, and maintenance, and designing buildings with a longer lifespan by opting for durable materials such as brickwork, stone, and post-consumer steel.
Transport
In Australia, cars are responsible for approximately half of the total greenhouse gas emissions attributed to transportation. The remaining emissions come from a combination of trucks, buses, aviation, railways, and shipping. Not only do these emissions contribute to climate change, but vehicle exhaust also contains harmful pollutants that pose significant health risks. As urban populations continue to grow, traffic congestion increases, leading to higher concentrations of exhaust pollutants and greenhouse gases in the air. Studies indicate that around 80% of Australian adults primarily rely on their cars for commuting. Our objective is to significantly reduce this statistic.
While government authorities are working on enhancing sustainable transportation alternatives such as public transit and bike lanes, we also anticipate active collaboration with private developers to promote these services. By reducing reliance on private car journeys, we can achieve several benefits, including lower overall construction expenses, reduced spending on fuel and car maintenance, improved air quality, which in turn reduces the prevalence of respiratory diseases, particularly among children and the elderly, enhanced health and fitness for individuals, and minimized greenhouse gas emissions, thereby supporting our community's environmental goals.
Waste Management
The construction and demolition sector contributes to about 40% of the waste in Australia's landfills. Additionally, the occupancy of buildings and daily consumption of goods generate a considerable amount of waste. Our past disregard for waste treatment has not only deteriorated our water, air, and land resources, but also imposed a significant financial burden on the present and future generations. Therefore, the pressing need to minimize, segregate, and recycle waste is increasingly evident. Efficient waste management can offer substantial social, economic, and environmental advantages. By reducing, recycling, and reusing waste, it's possible to decrease landfill waste, curb emissions, pollution, and contamination, conserve scarce resources, cut down construction costs and tipping fees, sell salvaged resources, and contribute towards your community's waste reduction targets set by the Council.
The most effective waste minimization strategies are those incorporated into a project's design stages and approved by all stakeholders. The building designers are the decision-makers in terms of waste minimization, including the choice of complete demolition or partial retention of an existing building. They also decide on the material use and construction techniques. Further decisions about the materials and their handling are made at the specifications stage, including which materials contain recycled content or could be recycled in the future, whether the materials and finishes are durable and maintainable, and if cut-offs and packaging can be recycled. At the contract documentation and tendering stage, it's crucial to develop a waste management plan outlining clear key performance indicators (e.g., a minimum total recycling rate), enabling all tenderers to incorporate best practice waste management into their pricing.
Urban Ecology
In heavily urbanized regions, like metropolitan Melbourne, acknowledging the significance of preserving and enhancing the health of our urban ecosystems is vital to improve living conditions for both us and the local fauna. Urban development in cities and suburbs has significantly changed natural environments and processes, impacting everything from soil drainage and waterway flows to light availability and wildlife habitats. For instance, the removal of vegetated areas and their replacement with hard surfaces, such as roads and pavements, exacerbates stormwater runoff and leads to flash flooding. These actions harm our landscapes, water bodies, and structures. However, there's a multitude of strategies we can implement in our urban regions to counteract the loss of natural processes and boost livability for humans, plants, and animals.
One of the simplest strategies involves reducing the extent of hard, impervious surfaces while simultaneously increasing vegetation and landscaping. Interestingly, studies suggest that landscaping in metropolitan areas can cut down air conditioning costs by as much as 50 percent by providing shade to windows and walls of buildings. Similarly, a single healthy tree can be as efficient as ten room-size air conditioners running for 20 hours per day. The advantages to our urban ecology are manifold, including temperature and noise reduction, enhanced air purification, and the creation of habitats for local fauna.
Innovation
Our current reality is grappling with the escalating issue of environmental pollution that threatens to severely degrade our quality of life. A myriad of innovative solutions, from renewable energy production systems to advanced building technologies, have been instrumental in shrinking our environmental impact. Despite significant strides in improving building efficiency, the consumption of energy, water, and various resources remains excessively high. The task before us now is to pioneer truly sustainable solutions for building design and construction. There exist numerous global instances showcasing how innovative design solutions can yield remarkable results, such as edifices that generate more energy than they consume. It's noteworthy that these innovative solutions not only result in highly efficient buildings but also enhance the living and working conditions within these spaces and often merit recognition for their architectural design.
The quintessential 'Australian Dream' has historically been associated with the image of a detached house on a generous property, encircled by a garden and providing ample space for extended family. While this lifestyle was feasible in the past, contemporary socio-economic shifts require the reimagining of the 'Australian Dream' for the 21st century. The sprawling nature of our cities has imposed both economic and infrastructural stressors due to the need to provide services to them. The extended travel distances between home, workplace, and school - whether by car or public transport - necessitate a heavy reliance on fossil fuels, thereby expanding our carbon footprint. As a result, it's time to embrace 'densification'. Historical precedents in European and Asian cities, as well as recent Australian projects, demonstrate that the quality of living spaces is not solely determined by their size. We can shift to a 'quality over quantity' mindset and expect more from the homes we create.
Construction & Building Management
Melbourne's landscape has seen a significant rise in the construction of green buildings in the past few years. These buildings, designed and built with the principles of environmental sustainability in mind, can actively contribute to reducing environmental harm. Still, the achievement of complete project success mandates sustainable site management and a guarantee that the green buildings perform as efficiently as originally designed. The pitfalls of poor construction management, a poorly executed handover process, delayed or ineffective maintenance, or a lack of understanding of building services can all lead to underwhelming outcomes, such as unexpectedly high energy and water consumption or unanticipated generation of construction waste, which can enlarge a building's environmental footprint. To truly realize a sustainable building through environmental design, the project must incorporate a robust and well-thought-out construction management approach and ongoing building management allowance. This includes early commitment to environmental targets, a waste minimisation strategy for demolition and construction, a waste segregation strategy during operation, regular tuning of building services, judicious use of building services like heating and cooling devices, and the preparation of a comprehensive Building Users Guide.
When selecting a designer, builder, or specialized contractor, we suggest evaluating their commitment towards sustainability. It can be useful to inquire about their previous project experiences in green building, their thoughts on individual eco-friendly initiatives, and any green certifications they possess. Various sustainability accreditation programs exist, such as the Master Builders Association's Green Living Builders, the Housing Industry Association's (HIA) GreenSmart Builders, Green Plumbers, and EcoSmart Electricians. Thermal Performance Assessors often have accreditation from either the Association of Sustainable Building Assessors (ABSA) or the Building Designers Association Victoria (BDAV). These accredited assessors have received training in building thermal performance assessment from a recognized training provider. We recommend not only securing a final rating for your permit application but also utilizing the modeling results to inform an enhanced building design. EcoSmart Electricians, accredited by the National Electrical and Communications Association (NECA), can identify cost savings, lower energy consumption, and reduce the overall environmental impact. Engaging experienced contractors and architects can ensure the effective implementation of these practices. The Green Building Council Australia (GBCA) accredits Green Star Accredited Professionals, supporting further sustainable building efforts.
Together we can make a Difference
In the face of rapid urbanization and environmental challenges, it is crucial that we integrate environmentally sustainable design principles at the core of our architectural and construction practices. This will enable us to address the pressing issues of our time and create a more sustainable future. Sustainability is no longer an option but a necessity, and it extends far beyond just energy and water efficiency. It encompasses virtually every aspect of the design, construction, and management of our built environment.
By reimagining our 'Australian Dream' with a focus on quality over quantity, leveraging innovation, and implementing robust construction and building management practices, we can significantly reduce our ecological footprint. Moreover, by choosing professionals with a proven commitment to sustainability, we can ensure that our buildings not only meet but exceed green standards.
As we move forward, let's strive for a future where buildings are designed and constructed with the planet's well-being as a priority. Remember, every small step towards sustainability can make a world of difference. Let's work together to create a greener and more sustainable future for the generations to come.