Carbon Footprints for Green Building Materials: Is It Common Practice in India?

Post date: Feb 10, 2013 4:16:24 PM

Vellaiappan asks: Is there any practice of calculating the carbon footprint of green construction materials in India to make buildings more eco-friendly and technically sound?

Advice provided by: Yusuf Turab, Y T Enterprises

Hi Vellaiappan. Many thanks for this question.

To answer your question in short: No, there is no practice of calculating carbon footprint information for building materials in India. It would be useful to have this information because customers would be able to make purchasing decisions based on how much energy the material consumed. However, there is no market-driven demand for publishing this information. I believe that this is because carbon footprints for materials are especially difficult to measure and are not always the best tool for identifying eco-friendly materials.

Carbon Footprints Are Difficult to Measure

Carbon footprints for building materials are difficult to accurately measure because they require a great deal of data. Some sectors, like transportation, only require a few variables – such as fuel burned per passenger. Building materials are especially difficult to evaluate because they are composed of many different raw materials and are made by various manufacturers who operate under constantly changing conditions.

For example, say you manufacture electric cables in the Indian state of Tamil Nadu. During peak season, 20% of Tamil Nadu's electricity comes from wind energy. That means that there is always a possibility that electricity demand in your factory is met partially through a renewable source, which has a much smaller carbon footprint than fossil fuel. However, there is no way for you to retrieve the data on the percentage of renewable fuel you’re using at any given moment or in any given season. Therefore, the carbon footprint for an individual electric cable will never be entirely accurate.

Carbon Footprint Tools for Building Materials

Measuring carbon footprints of building materials is not common practice, though some carbon footprint calculators do exist on the market.

I have heard that Australia has a program that measures the carbon footprints of the building materials harvested and manufactured within the country. (Perhaps someone can clarify this in the comment section below.)

Similarly, the Edinburgh Centre for Carbon Management (ECCM) has developed a tool called the Building Materials Carbon Indicator, which can be used to calculate the embodied carbon dioxide in building materials. This software tool can be accessed here. I have never used such a tool, but I assume the accuracy of the calculator's output depends on how much data you provide on the energy used to create the material.

Carbon Footprints and Environmental Impact

Carbon footprints are never a reliable environmental performance indicator when used alone. Many factors determine a material’s impact on the environment and the energy used to manufacture the material is only one of them. Therefore, carbon footprint information may not add much value to the environmental credentials of a building.

Let’s take lumber for example. The carbon footprint of regionally harvested lumber might be very low, nearly making it a carbon-neutral building material. However, the carbon footprint does not measure the other effects of cutting down trees, such as the loss of habitat, soil erosion, loss of carbon sink, heat island effect, etc. In some cases, a Forest Stewardship Council (FSC) Certified Wood will be better than another type of lumber with less embodied energy.

LEED and Carbon Footprints

Rating systems like LEED and GRIHA do partially address the embodied energy of building materials. They encourage contractors to use locally harvested and reused materials while discouraging the use of raw virgin materials. However, there is no real market-driven mandate that would encourage manufacturers to add embodied carbon dioxide to their products’ technical specifications sheets.

It would be useful if readers can share their experience in measuring carbon footprints of building materials in the comments section below.