Embodied Carbon in Building Construction
#00055
Even as operational building emissions decline through renewable energy and retrofits, the carbon embedded in construction materials — cement, steel, glass, insulation — remains a massive blind spot. Manufacturing cement alone produces 8% of global CO2. As cities renovate and build to meet climate targets, they risk creating a paradox: reducing operational emissions while increasing embodied emissions from the construction boom itself.
Parent issue
#00046 Urban Carbon Neutrality
Sustainable Development Goals
Location
global
Description
The construction sector is responsible for roughly 11% of global greenhouse gas emissions through material production alone — cement (8%), steel (7%), and other materials. These are "embodied" emissions: they occur during manufacturing and are locked in at the moment of construction, regardless of how efficiently the building operates afterward.
This creates a perverse dynamic in the net-zero transition. Aggressive renovation programs generate embodied emissions from new insulation, windows, and heating systems. New construction to replace aging, inefficient buildings carries even higher embodied carbon. The lifecycle calculation is complex: a deep renovation may produce more upfront emissions than continued operation of the old building, even if it saves operational emissions over decades.
The demolition question is central. Tearing down an existing building destroys the embodied carbon already invested in it and generates massive new emissions for the replacement. Yet demolition is often cheaper and simpler than deep renovation, creating a market bias toward teardowns.
Measurement and regulation are catching up. France's RE2020 regulation (in force since 2022) mandates lifecycle carbon assessment for all new buildings with progressively tightening limits. Denmark's BR18 introduced a whole-life carbon limit of 12 kg CO2e/m2/year in 2023, tightened to 7.1 in 2025. Switzerland is now requiring cantons to set embodied carbon limits of 12–13 kg CO2-eq/m2/year.
The solutions are known — timber construction, low-carbon concrete, material reuse, bio-based insulation — but scaling them requires both regulation to create demand and investment in alternative supply chains.