What does a hut, an igloo and a bamboo shack have in common? They are primitive and are green buildings. Back then, that was all the material that was available to build shelters. Such dwellings still exist on this planet. People didn’t know they were building ‘green buildings’ because they didn’t have to bother. But now considering the rate at which buildings are made, it is a necessity to keep a check on its side effects.
Keeping a check on the consequences of constructing innumerable dwellings is just one side of the coin. The other side of the coin represents learning from nature. Mick Pearce, an African architect was inspired by the ingenuity of termite homes. These homes always have their internal temperature maintained. They are strong and durable. How is this possible? The answer lies in its engineered structure – the shape and the way air flows (convection) inside; the application of which now stands tall in Zimbabwe – The Eastgate Centre.
Are our current buildings green? Not all. But people have studied these buildings and put together a few things to make them greener. When judging the greenness of an existing building or when we have to build a new one, one has to consider an entire life cycle of the building. This life cycle assessment (LCA) includes:
- Materials needed for constructing the entire building
- How the materials were procured
- Design of the building
- Operation and how it responds to atmospheric conditions
During this life cycle analysis, one can measure:
- carbon dioxide emissions
- energy consumption
- waste produced
- resource consumption such as water
- pollution caused
To give an example, we can think of net-zero energy buildings. Net-zero energy buildings (aka zero-energy building, zero net energy (ZNE) building, net-zero energy building (NZEB), or net zero building), wherein zero signifies no carbon emissions. Although initial costs of these buildings are higher, ZNE buildings are sustainable and hence a wise long term strategy. But where do carbon emissions come from in a construction industry? An entire life cycle of this industry shows that GHG emissions come from the following areas of the process:
- Materials of construction (The manufacture of which depends on energy and energy comes from fossil fuels on a large part.)
- Construction on-site processes (This would need energy.)
- Associated transport/ Distribution (Transport means fuel, simple.)
- In-Use operations that is use of lighting, air conditioning: heating or cooling.
- Demolition and waste handling (When everything is done, even demolishing it requires energy.)
These areas are common to both commercial as well as residential buildings. What can be done to countermeasure the effect of such consumption? One way is to adopt solar power. Buildings can be fitted with solar panels for in-use operations that account for the largest proportion, over 80%, of total CO2 emissions in this industry. To the rescue now smartphone apps that homeowners can use to energy audit their homes on their own. Existing buildings can be fitted with solar panels or can be provided with an external insulation depending on the local climate conditions.
To regulate this entire process, standards have been laid down and vary from country to country. In the USA, for instance, LEED (Leadership in Energy and Environmental Design) provides ratings which help builders and owners construct a green building.
This blog post was first published at GreenHatters on February 15, 2014. Version edited for minor corrections.
GreenHatters is a not-for-profit initiative that cares for the environment and promotes sustainability, strives to create awareness on Energy conservation and Carbon footprint responsibility.