Myth-busting embodied carbon: 10 misconceptions slowing decarbonization in construction

Why It Matters

Buildings account for 37 percent of global energy-related CO₂ emissions, and embodied carbon, the emissions locked into materials, transport, and construction processes, represents a growing share of that total. As operational energy efficiency improves through better insulation, heat pumps, and renewable electricity grids, embodied carbon's relative contribution is rising fast. For new buildings constructed to current codes, embodied carbon can represent 50 to 80 percent of total lifecycle emissions over a 60-year horizon (World Green Building Council, 2025). Yet persistent myths about measurement difficulty, cost, and material performance continue to slow action. A 2025 survey by the Carbon Leadership Forum found that 58 percent of architects and engineers cited misconceptions about embodied carbon as a barrier to adopting reduction strategies. Clearing away these myths is essential if the construction sector is to meet its Paris-aligned targets.

Key Concepts

Embodied carbon refers to the greenhouse gas emissions associated with materials and construction processes throughout the whole lifecycle of a building. This includes raw material extraction (A1), transport to manufacturing (A2), manufacturing (A3), transport to site (A4), construction (A5), maintenance and replacement (B1-B5), and end-of-life demolition, transport, and disposal or recycling (C1-C4). Module D captures benefits beyond the system boundary, such as material reuse or energy recovery.

Life Cycle Assessment (LCA) is the methodology used to quantify embodied carbon, standardized under ISO 14040/14044 and applied to buildings through EN 15978 (whole building) and EN 15804 (product level via Environmental Product Declarations, or EPDs).

Environmental Product Declarations (EPDs) are standardized, third-party-verified documents that report the environmental impact of a product. They are the primary data source for building-level embodied carbon calculations. The EC3 (Embodied Carbon in Construction Calculator) tool developed by Building Transparency now contains over 150,000 EPDs globally (Building Transparency, 2025).

Global Warming Potential (GWP) measured in kilograms of CO₂-equivalent (kgCO₂e) is the standard metric for embodied carbon. Benchmarks are typically expressed per square meter of gross floor area (kgCO₂e/m²).

The 10 Myths

Myth 1: Operational carbon always dwarfs embodied carbon, so embodied carbon can wait

This was true when buildings were poorly insulated and heated with fossil fuels. It is no longer the case. Research by the Royal Institution of Chartered Surveyors (RICS, 2024) shows that for new buildings designed to current energy codes, embodied carbon accounts for 50 to 70 percent of whole-life carbon. In low-energy buildings such as Passivhaus-certified structures, that share rises above 80 percent. As electricity grids decarbonize (the UK grid intensity fell 78 percent between 2012 and 2025 according to National Grid ESO), operational carbon will shrink further, making embodied carbon the dominant challenge. Delaying action means locking in emissions for decades.

Myth 2: Measuring embodied carbon is too complicated and expensive for most projects

Modern tools have dramatically lowered the barrier to measurement. One Click LCA, Tally, and the open-access EC3 calculator allow designers to estimate embodied carbon in hours, not months. One Click LCA reports that its users complete a whole-building LCA in an average of 16 hours, often integrated directly into BIM workflows via Revit and IFC plugins (One Click LCA, 2025). The cost of a professional whole-building LCA ranges from $5,000 to $25,000, a fraction of a percent of total construction costs. The RICS Whole Life Carbon Assessment standard (2nd edition, 2023) provides a clear, step-by-step methodology that any competent design team can follow.

Myth 3: There is not enough EPD data to do meaningful calculations

The EPD ecosystem has grown exponentially. Building Transparency's EC3 tool now indexes over 150,000 EPDs from more than 40 countries (Building Transparency, 2025). The European Commission's InData platform and national EPD program operators (IBU in Germany, EPD International in Sweden, INIES in France) collectively publish thousands of new declarations each year. For products without manufacturer-specific EPDs, industry-average data from databases such as ICE (Inventory of Carbon and Energy, University of Bath) and Ecoinvent provide defensible estimates. Data coverage for high-impact categories like concrete, steel, insulation, and cladding is now robust in most major markets.

Myth 4: Switching to low-carbon materials always costs significantly more

The "green premium" for low-carbon materials is frequently overstated and declining rapidly. A 2025 Boston Consulting Group analysis found that low-carbon concrete (using supplementary cementite materials like GGBS or fly ash) costs 0 to 5 percent more than conventional mixes in most markets, and in some cases is cheaper because of reduced cement content (BCG, 2025). Low-carbon steel produced via electric arc furnace (EAF) with recycled scrap is already price-competitive with blast furnace steel in many regions. Cross-laminated timber (CLT) can reduce structural embodied carbon by 40 to 60 percent versus reinforced concrete, and while material costs may be higher, total installed costs are often comparable due to faster erection times and reduced foundation loads. Skanska's research across 30 projects found that a 30 percent embodied carbon reduction was achievable at zero to two percent cost uplift through material optimization alone (Skanska, 2024).

Myth 5: Timber is always the lowest-carbon structural option

Mass timber products such as CLT and glulam offer significant embodied carbon advantages over steel and concrete, but the picture is more nuanced than marketing suggests. The carbon benefit of timber depends critically on forestry practices, transport distances, end-of-life scenarios, and whether biogenic carbon storage is credited. The EN 15804+A2 standard treats biogenic carbon as a separate flow: carbon is stored in module A (a negative emission) but released at end of life in module C if the timber is incinerated. If the building is demolished and the timber is burned for energy or sent to landfill, the storage claim evaporates. A 2024 study published in the Journal of Cleaner Production found that when end-of-life incineration was assumed, the lifecycle GWP advantage of CLT over concrete reduced by 35 to 50 percent (Hafner & Schäfer, 2024). Timber's carbon benefits are real but contingent on sustainable sourcing (FSC or PEFC certification), long service life, and circular end-of-life pathways such as reuse or cascading.

Myth 6: Embodied carbon regulations are years away and not worth preparing for

Regulation is arriving faster than many in the industry expect. France's RE2020, effective since 2022, mandates whole-life carbon limits for all new buildings with progressively tightening thresholds through 2031. The Netherlands' MPG (Milieu Prestatie Gebouwen) system has required environmental performance calculations since 2018 and tightened limits in 2025. Denmark introduced a 12 kgCO₂e/m²/year limit for new buildings over 1,000 m² in 2023, dropping to lower thresholds by 2025. The Greater London Authority requires whole-life carbon assessments for all referable planning applications. In the United States, the Buy Clean California Act mandates EPDs and sets GWP limits for structural steel, concrete, flat glass, and mineral wool insulation in state-funded projects. The federal Buy Clean Task Force (2024) expanded similar requirements to federally funded infrastructure. Companies that wait for regulation to arrive before building measurement capacity will face a steep and expensive learning curve.

Myth 7: Recycled content automatically means low embodied carbon

Recycled content reduces embodied carbon for many materials, particularly metals, but the relationship is not automatic. Steel produced via EAF with 90 percent recycled scrap has roughly 50 to 75 percent lower GWP than basic oxygen furnace (BOF) steel, depending on the electricity source powering the EAF (World Steel Association, 2025). However, recycled aluminum smelted with coal-heavy electricity can have higher emissions than primary aluminum produced with hydropower. Similarly, recycled aggregate concrete does not always have lower GWP than virgin aggregate concrete because the cement content (the dominant carbon driver) typically remains the same. What matters is the combination of recycled content, manufacturing energy source, and overall mix design. Always check the EPD rather than relying on recycled content percentages as a proxy for carbon performance.

Myth 8: Offsetting can compensate for high embodied carbon

Carbon offsets can play a limited role in a net-zero strategy, but they are not a substitute for reducing embodied carbon at source. The Science Based Targets initiative (SBTi) requires companies in the buildings and construction sector to reduce absolute Scope 1 and 2 emissions by at least 42 percent by 2030 and pursue deep Scope 3 reductions. Offsets are only accepted for residual emissions after all feasible reductions have been made. From a physical standpoint, embodied carbon is emitted at the point of material production and construction. Unlike operational emissions, which recur annually and can be reduced through retrofits, embodied carbon is locked in at completion. A building with 500 kgCO₂e/m² of embodied carbon releases those emissions immediately; purchasing offsets does not reverse the atmospheric impact. The UK Green Building Council's Net Zero Carbon Buildings Framework (2024) explicitly requires embodied carbon measurement and reduction before any residual offsetting.

Myth 9: Only structural materials matter for embodied carbon

Structure (foundations, frame, floor slabs) typically accounts for 40 to 60 percent of a building's embodied carbon, which means 40 to 60 percent comes from other sources. Facades, cladding, MEP (mechanical, electrical, plumbing) systems, finishes, and fitouts contribute substantially. A 2025 analysis by Arup across 50 commercial office buildings found that MEP systems alone accounted for 15 to 25 percent of whole-life embodied carbon, while interior finishes contributed 10 to 20 percent (Arup, 2025). Over a 60-year lifecycle, replacement cycles for cladding, HVAC equipment, and interior fitouts can double their initial embodied carbon contribution. Focusing solely on structural materials misses significant reduction opportunities in specification of insulation, glazing, ceiling systems, raised floors, and building services.

Myth 10: Embodied carbon reduction is only relevant for new buildings

Renovation and retrofit projects also carry significant embodied carbon implications. A whole-building LCA comparing deep retrofit versus demolition and new-build consistently shows that retrofitting avoids 50 to 75 percent of the embodied carbon of new construction, even after accounting for the carbon cost of retrofit materials (Historic England & Sturgis Carbon Profiling, 2024). The concept of "carbon payback period" applies: a new, operationally efficient building must operate for decades before its operational savings offset the upfront embodied carbon of demolition and reconstruction. For existing buildings, specifying low-carbon retrofit materials (mineral wool vs. spray foam, lime mortar vs. OPC-based products, refurbished steel vs. new) offers meaningful reduction opportunities. The decision to demolish or retrofit is itself an embodied carbon decision, and increasingly, planning authorities require a whole-life carbon comparison before granting demolition consent.

Action Checklist

• Mandate whole-life carbon assessments at RIBA Stage 2 or equivalent for all projects, not just those above regulatory thresholds
• Specify EPDs for all major material categories and use tools like EC3, One Click LCA, or Tally to compare options
• Set embodied carbon targets using benchmarks from LETI, RIBA 2030 Climate Challenge, or regional regulatory limits
• Optimize structural design to reduce material quantities before switching materials (the cheapest and lowest-carbon kilogram is the one you do not use)
• Evaluate low-carbon concrete mixes (GGBS, fly ash, calcined clay) and request manufacturer-specific EPDs from suppliers
• Assess timber sourcing carefully: require FSC or PEFC certification and model end-of-life scenarios explicitly in LCA
• Include MEP systems, finishes, and fitout materials in embodied carbon calculations
• Favor renovation and adaptive reuse over demolition wherever structurally and functionally feasible
• Track and disclose embodied carbon in CSRD, ISSB, or voluntary reporting frameworks
• Build internal capacity through Carbon Leadership Forum training, RICS whole-life carbon competency, or equivalent programs

FAQ

What is a good embodied carbon benchmark for a new building? Benchmarks vary by building type and region. LETI (London Energy Transformation Initiative) recommends less than 350 kgCO₂e/m² (A1-A5 only) for new residential buildings and less than 600 kgCO₂e/m² for commercial offices as a 2025 target, with a pathway to below 250 and 400 kgCO₂e/m² respectively by 2030. Denmark's regulatory limit of 12 kgCO₂e/m²/year (annualized whole-life over 50 years, equating to roughly 600 kgCO₂e/m² total) provides another reference. The most important step is to benchmark against peers and set a project-specific target, then track performance through design stages.

Can BIM tools calculate embodied carbon automatically? Increasingly, yes. Plugins like One Click LCA for Revit and Tally for Revit extract material quantities directly from the BIM model and link them to EPD databases. This automates much of the calculation process, though professional judgment is still needed for material specifications, end-of-life scenarios, and data quality checks. IFC-based workflows allow interoperability across software platforms. Firms like Henning Larsen and Foster + Partners have integrated embodied carbon dashboards into their standard BIM workflows since 2024.

Is carbon capture in concrete (carbon curing) a game changer? Technologies like CarbonCure, Solidia, and CarbiCrete inject captured CO₂ into concrete during mixing or curing, mineralizing it permanently. CarbonCure reports savings of approximately 16 to 25 kgCO₂ per cubic meter of concrete, which represents a 5 to 8 percent reduction in typical concrete GWP (CarbonCure, 2025). This is meaningful but not transformative on its own. The largest lever for concrete decarbonization remains cement substitution (GGBS, fly ash, calcined clay), which can reduce concrete GWP by 30 to 50 percent. Carbon curing is best understood as a complementary strategy, not a silver bullet.

How do I account for biogenic carbon in timber? Follow EN 15804+A2, which requires biogenic carbon to be reported as a separate information module. Carbon uptake during tree growth is reported as a negative value in module A1. Carbon release at end of life (incineration, decay) is reported in module C3 or C4. If the timber is reused or recycled, benefits are captured in module D. Avoid double-counting by not combining biogenic carbon with fossil GWP into a single number without disclosure. Whole-building LCA tools like One Click LCA handle this automatically when configured correctly.

What is the biggest single lever for reducing embodied carbon? Design efficiency and material optimization consistently deliver the largest reductions. Reducing the volume of concrete in foundations (through geotechnical optimization), specifying efficient structural grids, eliminating transfer structures, and right-sizing MEP systems can cut embodied carbon by 20 to 30 percent before any material substitution. After design optimization, cement substitution in concrete and use of high-recycled-content or renewable materials offer the next largest gains. The hierarchy is: build less, build clever, build with low-carbon materials.

Sources

• World Green Building Council. (2025). Bringing Embodied Carbon Upfront: Coordinated Action for the Building and Construction Sector. WorldGBC.
• Carbon Leadership Forum. (2025). Industry Survey: Barriers to Embodied Carbon Reduction in Architecture and Engineering Practice. University of Washington.
• RICS. (2024). Whole Life Carbon Assessment for the Built Environment (2nd Edition). Royal Institution of Chartered Surveyors.
• Building Transparency. (2025). EC3 Tool: Global EPD Coverage and Platform Statistics. Building Transparency.
• One Click LCA. (2025). Platform Usage Report: Average Assessment Time and BIM Integration Metrics. One Click LCA Ltd.
• Boston Consulting Group. (2025). The Green Premium Tracker: Low-Carbon Construction Materials Cost Comparison. BCG.
• Skanska. (2024). Embodied Carbon Reduction Across 30 Projects: Cost and Performance Analysis. Skanska AB.
• Hafner, A. & Schäfer, S. (2024). End-of-Life Scenarios and Biogenic Carbon in Mass Timber Buildings: A Comparative LCA. Journal of Cleaner Production, 434, 139876.
• World Steel Association. (2025). Steel Sustainability Indicators: EAF vs. BOF Carbon Intensity by Region. World Steel Association.
• Arup. (2025). MEP and Fitout Embodied Carbon: Analysis Across 50 Commercial Office Buildings. Arup Group Limited.
• Historic England & Sturgis Carbon Profiling. (2024). Retrofit vs. Demolition: Whole-Life Carbon Comparison for Heritage and Non-Heritage Buildings.
• CarbonCure Technologies. (2025). CO₂ Mineralization in Ready-Mix Concrete: Performance Data and EPD Results. CarbonCure Technologies Inc.
• UK Green Building Council. (2024). Net Zero Carbon Buildings Framework: Definition, Methodology and Reporting Requirements. UKGBC.