Embodied vs. Operational Carbon Crossover

Every building carries a fixed embodied-carbon debt from the materials used to build it, and a recurring operational-carbon cost from every year it is heated, cooled and lit. This 2D companion plots the flat embodied-carbon line against the rising cumulative-operational-carbon line and marks the exact year the two cross — the point where a building's ongoing energy use has emitted as much CO₂ as its construction did. Switch between a concrete tower, a mixed-mass building and a mass-timber design to load realistic embodied-carbon baselines, then drag the embodied carbon, annual operational carbon and lifespan sliders to watch the crossover point move.