Whole life carbon is the sum of all the emissions generated by a building throughout its existence, from the manufacture of materials to demolition and waste management. It is divided into two categories: operational carbon, associated with the daily consumption of the building (air conditioning, ventilation, lighting), and embodied carbon, contained in the production, transport, construction and end of life of materials.

As new buildings become more efficient in the use phase, the relative weight of embodied carbon grows. In high-efficiency new buildings, it can account for half of the emissions of the entire life cycle, a part that is often left out of the calculation because it was generated before the building came into operation.

The practical consequence is clear: the decisions that most condition the footprint of a building are made in the design phase, when the shape, structure, materials and systems can still be chosen. That is why the life cycle analysis must be part of the initial specification of the project, and not be a calculation that is made at the end to justify a certification. Measuring in time is what allows us to decide.