A Carbon Bill for Every Building

For decades, the climate story of a building began on the day it opened. Insulation, heat pumps and solar panels all reduce the energy a building uses in operation, and rules have pushed hard in that direction. But a large part of a new building's lifetime emissions happen before anyone moves in: in the cement, steel and glass, and in getting them to site.1

These are called embodied emissions, and they are paid upfront. A building can be very efficient to run and still have cost the atmosphere a great deal to make. Demolishing an old building to put up an efficient new one can take decades to pay back.

The idea now circulating among city officials is simple to state. Before a permit is granted, every project should calculate its embodied carbon and publish it, like a price tag. In time, a limit would be set and slowly lowered.2 Projects that reuse existing structures would score well almost automatically.

Developers worry about cost and paperwork. Architects worry about tools that reward clever accounting over good buildings. Both are fair worries. But the alternative, carrying on without counting, has already given us a construction industry that produces a large share of the world's emissions while calling itself green.