Global Whole Life Carbon Tracker for the Built Environment

Context

The IEA, UNEP and the IPCC have spent two decades attributing somewhere between 21% and 37% of global CO₂ emissions to building construction and operation. Despite that scale, the IEA’s Clean Energy Progress tracker still classifies buildings as “more efforts needed”, and building envelopes as “not on track”. As energy systems decarbonise and operational emissions fall, it is the embodied emissions, from materials, construction, maintenance, renovation and end of life, that increasingly decide the climate impact of a building.

Embodied carbon remains less well understood, less consistently reported and less well governed than operational emissions. Global building emissions data exists only at an aggregate level, or for subsets of the stock such as residential buildings or fossil energy demand. Without a picture of where the sector actually starts from, and of how far apart those starting points are given different construction practices, material use and climates, there is no basis for a common definition of what a “low carbon building” even is. Clear data and clear definitions are the precursors to moving investment.

This project was commissioned as a follow-up to the 10 Whole Life Cycle Recommendations for the Built Environment, published by the GlobalABC Materials Hub in 2024 and developed through a consensus process with more than 100 experts from 40 countries. It supports Recommendations 3, 4 and 6: increasing access to geographically representative data and benchmarks, so that investment in reducing embodied emissions has something to aim at.

Objectives

Build a framework that can be re-run. A robust and updateable method for estimating and tracking embodied carbon from new building construction globally, situated against the wider evidence base on existing buildings and renovation. A tracker that cannot be repeated next year is not a tracker.
Resolve the world into 12 regions. Differentiating embodied emissions across 12 world regions, which is what makes it possible to show where emission profiles genuinely differ and where the data is simply weaker.
Model around the data gaps rather than through them. A hybrid approach combining bottom-up building archetype modelling with top-down material and economic datasets, because neither alone covers the globe.
State the uncertainty as a range, not a number. Estimates for a 2024 reference year, explored under a moderate and an upper-end material use scenario, so the uncertainty in material demand is visible rather than averaged away.
Test what policy would actually change. The effect of material decarbonisation policies, set against the current policy trajectory and against a 1.5 °C aligned material emissions pathway.