A review of the literature on green building will make it clear that there are a wide variety of interpretations available. Some are very technocratic whereas others refer to new age mystical ideas! Rarely is a holistic approach adopted in which every aspect of environmental impacts is considered.
Some see environmental issues as only about saving energy or improving building services. Many people associate green building with adding renewable energy to buildings and adopting micro generation. In many cases the materials that are used are fairly low down on the list of concerns for the designer or client. On the other hand some advocate using straw-bales and mud to create low impact buildings with purely natural materials.
This plurality of approach can also be found when looking at environmental assessment tools and methods. Some are concerned with assessment systems for buildings and others for materials as though they are two different things when in fact they are completely inter-related. The other difference is whether assessment tools are to design buildings or assess them once they are built. If assessment systems are not useful as design tools, then they are essentially measuring the impact once the damage has been done.