Consuming over 40% of total Energy generated, it is fair to say that buildings have both a direct and indirect impact on the environment, whether during the construction, occupation or demolition phases.

The huge negative impact of buildings on the environment has led to a situation where there is now a proliferation of rating and certification tools and systems from B REEAM in the UK, LEED in the US and Passivhaus in Germany. They  are aimed at guiding, demonstrating and documenting how sustainable and energy efficient buildings should be delivered.

One of the tools I have personally found to be among the best is the Edge (Excellence in Design for Greater Efficiency ).

Edge is a collaboration between the world green building council (WGBC) and the International Finance Corporation (IFC) which happens to be a member of the world bank group. In partnering with the WGBC,  The IFC has found a way of accelerating construction of green building in developing countries. From its website, it boldly proclaims that  "it has recognised the central role that buildings play in mitigating climate change, creating jobs and improving the living conditions of millions of people" especially in emerging markets.

What I find most intriguing about EDGE is the ease with which a building can be certified. What has traditionally been a cumbersome and expensive process with existing rating tools has suddenly become a breeze with EDGE.

With EDGE, there are three main resource categories; Energy, Water and Material. A building has to achieve a reduction of 20% in all three categories to be certified. The 20% reduction is measured against a base level which is how any of the resource categories is consumed in the country where the assessment is being undertaken by a similar building. So for example countries in temperate climates may use more gas for space heating, hence if they they can reduce their gas consumption by they are more likely to achieve a Total Energy reduction of 20%. The metrics for a country like Ghana where heating is not a major consideration will be considerably different.

Unlike other rating systems, edge does not rely on the acquisition of credits but rather relies on a simple pass or fail system. There are no levels of achievement, the building either meets a particular criteria or it doesn't. Other factors like indoor air quality or acoustics as important as they are, are not considered. Not because they are not necessary but mainly because their effect on the total energy and water use in a building is quite negligible.

Edge is not perfect and definitely not for everyone but if you need a fast, affordable and simple rating tool that already has energy and climatic data available for your project then IFC's EDGE is worth looking at.