Introduction
Why do we need to rethink the current development approach?
Global context
Globally, 40 per cent of all energy and material resources are used to build and operate buildings, 40 per cent of greenhouse gas emissions come from building construction and operation, and 40 per cent of total waste results from construction and demolition activities (United Nations Environment Programme [UNEP], 2007). Compounding these figures are further impacts on land, water and air quality, as well as human health.
The impacts on the environment result from pollutants, energy and water use, land degradation and use, resource use, waste production and loss of biodiversity. These occur throughout the life cycle of buildings – from raw material extraction, processing, construction, building operation and maintenance, through to demolition.
In 2003, the United Nations warned that if current patterns did not change, the expansion of the built environment would destroy or disturb natural habitats and wildlife on more than 70 per cent of the Earth’s land surface by 2032 (UNEP Industry and Environment, 2003). In 2005, the Millennium Ecosystem Assessment warned that human activity was putting such a strain on the natural functions of the Earth that the ability of the planet’s ecosystems to sustain future generations could no longer be taken for granted (MEA, Living Beyond Our Means, 2005).
William Rees, the originator of the ‘ecological footprint analysis’ concept, contends that no other industrial sector has greater opportunity and none is better positioned to lead the quest for global sustainability than the building and construction sector. It is not surprising then, that UNEP sees the building and construction sector as having more potential to contribute to achieving sustainability than any other sector (UNEP, 2007).
The New Zealand context
In the New Zealand context, the built environment includes both urban and rural elements. Its scale varies from small provincial towns to medium-sized cities.
Given the current rate of building and demolition in New Zealand, what we have in 2009 will mostly still be in place in 50 years’ time. That means the continued development of a sustainable built environment will largely involve retrofitting of existing buildings and infrastructure.
The built environment in New Zealand has wide-ranging, negative environmental impacts, including contribution to climate change, reduced air quality, high water and energy use, high materials use and waste. While more work needs to be done to measure the environmental impacts of New Zealand buildings, it has been estimated that our building stock is responsible for:
- 45 per cent of total electricity use – 22 per cent commercial, 23 per cent residential
- 17 per cent of total carbon dioxide emissions – 8 per cent commercial, 9 per cent residential
- 50 per cent of waste (construction and demolition waste going to landfill and cleanfill).
More research is also needed to quantify the environmental impacts associated with raw material extraction, manufacture and transport.
Awareness is growing, particularly over the last five years, of the importance of a sustainable built environment that addresses these negative impacts and increases the quality of the built environment. This awareness is reflected in initiatives, including the New Zealand Urban Design Protocol, the New Zealand Green Building Council and the Green Star environmental rating scheme for buildings, the Building Code review, and built environment sustainability research consortiums, such as Beacon Pathway.
Central and local government are responsible for approximately 30 per cent of all construction in New Zealand. In this context, central government organisations collectively play a critical role in shaping New Zealand’s built environment. By changing our development approach to one more aligned to sustainability, we have a great opportunity to make meaningful changes to the way New Zealanders plan, design, construct and use our built environment.
Business-as-usual is changing
Business-as-usual in the New Zealand built environment has included conventional approaches to building design, and green or high performance building design, termed here as eco-efficiency.
Eco-efficiency means creating the same or more goods and services while using fewer resources and producing less waste and pollution. Ultimately, eco-efficiency looks to achieve neutral environmental impact, but does not seek to achieve positive environmental effects. However, the long-term outcome of simply reducing, rather than reversing, negative environmental impact will be that ecosystems that support healthy human communities and economies will continue to degrade over time, although presumably at a slower rate.
Most existing and newly constructed buildings in New Zealand take into account few, if any, environmental sustainability issues in their design or use. Even among central government organisations, the adoption of environmentally sustainable design practices has been slow, and still remains patchy across the programme.
However, change has begun. The growing adoption of environmentally sustainable design principles and practices means more new buildings are being designed this way, driven in part by increased market demand. Central government organisations are contributing to this change.
Factors influencing the increasing market demand may include ‘green’ buildings’ lower operating costs, increased occupant satisfaction and health, readily accessible guidance on environmental standards provided by the New Zealand Green Star rating tools, an increased desire to address environmental issues, and a global trend towards sustainable building.
