There have been so many inquiries about our carbon calculator work that we wanted to explain how we get at the total impact of a building, including the supply chain of the occupant company.
Below is a calculator specifically for the farm-to-customer value chain (kudos to our colleague Kumar Venkat for crafting of this calculator), as you would find with buildings with a restaurant or cafe. To get a complete picture of the carbon footprint, you have to take into account the GIG sources at the farm level. You have to understand the transportation network, looking at both modes of travel (truck, ship, etc) as well as all the nodes (various stopping points). You have to understand the processing energy, whether that's in packaging, cooking, or at restaurant level. The calculator charts the impacts in different areas, and allows you to adjust distance, amount, and the amount of waste (which has ripple effects up the supply-chain)
Please play around and see how footprint changes as you change the scenario.