The climate change indicator is used to assess a construction product or equipment’s contribution to the increased content of greenhouse gases in the atmosphere. It is generally accepted that the increasing greenhouse effect causes changes to the Earth’s climate, notably an increase to its average temperature. It is expressed in kg CO2 equivalent (carbon dioxide or carbonic gas) and includes all of the greenhouse gases that the product emits over the course of its life cycle. Not all gases have the same effect.
For example, a kilogram of methane (CH4) contributes 21 times more to the greenhouse effect than a kilogram of CO2, and one kilogram of nitrous oxide (N2O) is 310 times more harmful. Per kilogram emitted, some gases contribute several thousand times more to the greenhouse effect than CO2. Thus, the climate change indicator provides information on greenhouse gas emissions and their impact on global warming. The standard requires that at least the three main gases relevant to construction products (CO2, CH4, N2O) be taken into account.
While many tools exist for evaluating a territory or activity’s greenhouse gas emissions (carbon footprint or carbon accounting, etc.), life cycle analysis (used in the FDES and PEP) is the only tool adapted to both products and buildings.
As for energy, it is important to think on the scale of the building rather than the products because some products benefit the building by reducing its consumption and greenhouse gases emissions. To avoid counting this effect twice, avoidances are not attributed to products but are included in the environmental and energy performances of buildings.