GREEN BUILDINGS

Why go Green?

Ecologically sustainable design (ESD) or 'Green Building' can significantly reduce adverse human impacts on the natural environment while simultaneously improving quality of life and economic well being. The demand for energy efficiency, reduction of green house gases, sustainable use of building materials and healthy building environments, is set to increase in the future. In NSW, the building sustainibility index, BASIX , requires that new buildings meet a range of sustainability indicies such as Landscape, Stormwayer, Water, Thermal Comfort and Energy. BASIX is a web-based planning tool designed to assess the water and energy efficiency of new residential developments at the design stage, developed by the NSW Department of Planning. NatHERS and AccuRate are simulation packages used to assess the potential energy performance of the fabric of a house, based on the layout and materials used.

Rather than resist these changes, the building industry has sought to encourage 'Green Buildings' by providing a rating system that sets apart buildings that are more efficient, cheaper to run and result in lower green house gas emissions. These are the buildings that command a higher value, not just in the community, but also in the marketplace.

Currently there are two ratings systems; The Green Building Council of Aust (GBCA) Green Star environmental rating system and the National Built Environment Energy Rating System (NABERS). Both rating systems require rating or assessment by accredited/certified assessors.

Green Building Council of Aust (GBCA) 
www.gbca.org.au 

The Green Building Council of Australia launched the Green Star environmental rating system for buildings in 2003. Green Star rating tools help the property industry to reduce the environmental impact of buildings, improve occupant health and productivity and achieve real cost savings, while showcasing innovation in sustainable building practices.

For example, for a multi residential unit building to gain a favourable green star rating, it must achieve a minimum performance based on the following criteria and percentage weightings:

  • Management ____________ 8%
  • Indoor air quality_________ 20%
  • Energy_________________25%
  • Transport_______________10%
  • Water__________________15%
  • Materials_______________10%
  • Land use & Ecology ______ 7%
  • Emissions_______________5%
National Australian Built Environment Rating System (NABERS)
www.nabers.com.au 

NABERS - the National Australian Built Environment Rating System - measures an existing building's environmental performance during operation. NABERS rates a building on the basis of its measured operational impacts and provides a green star rating based on the following impact categories.

Energy use and greenhouse emissions - Energy-related greenhouse emissions are a key factor in increasing the levels of carbon dioxide in the atmosphere, leading to human induced climate change. How buildings are operated can affect their energy demand significantly.

Water use - Building users can be major water consumers, but users can also adopt practices to harvest water sustainably and effect considerable reductions in demand on existing constrained supplies.

Waste - Waste contributes to resource depletion and a range of pollutants and emissions. The reduction of waste minimises the area needed for landfill, and reduces the environmental impact of overall materials throughput.

Indoor environment - As well as minimising impacts to the wider environment, It is important for the health, satisfaction and productivity of occupants that buildings provide a comfortable indoor environment for those who use them.

Currently NABERS provides separate ratings for Office Buildings, Office Tenanacy's, Hotels and Homes. Ratings are in development for hospitals, schools and retail centres.

 

Recommended Reading

Cradle to Cradle by William McDonough & Michael Braungart - North Point Press

"Architect McDonough and chemical engineer Braungart explain how products can be designed from the outset, so that after their usefull lives, they will become nourishment for something new. They can be conceived as biological nutrients that will easily re-enter the water or soil without depositing synthetic materials and toxins. Or they can be technical nutrients that will continually circulate as pure and valuable materials within closed industrial cycles"