Case study: Embodied carbon reduction — a developer's journey from measurement to 40% reduction

Why It Matters

Buildings account for roughly 37 percent of global energy-related carbon emissions, and embodied carbon from materials, transport, and construction now represents up to 50 percent of a new building's whole-life carbon footprint (UNEP, 2024). As operational energy efficiency improves through electrification and tighter building codes, the relative share of embodied carbon keeps growing. The World Green Building Council (2024) estimates that embodied carbon must fall by at least 40 percent before 2030 to keep the sector aligned with a 1.5 °C pathway. For commercial developers managing multi-asset portfolios, ignoring embodied carbon means locking in decades of unmitigated emissions at the point of construction. Regulations are catching up: the EU Level(s) framework, London's GLA planning guidance, and emerging CSRD requirements all demand whole-life carbon assessments. Developers that move early gain procurement leverage, regulatory readiness, and competitive positioning with institutional investors increasingly screening for Scope 3 construction emissions.

Key Concepts

Whole-life carbon assessment (WLCA). WLCA covers emissions across all life-cycle stages defined in EN 15978: product stage (A1 to A3), construction process (A4 to A5), use stage (B1 to B7), and end-of-life (C1 to C4). Upfront embodied carbon, stages A1 to A5, is the primary lever for developers because these emissions are released before the building is occupied and cannot be offset through operational improvements.

Carbon intensity benchmarks. Embodied carbon is expressed in kilograms of CO₂ equivalent per square metre (kgCO₂e/m²). The RIBA 2030 Climate Challenge sets targets of 600 kgCO₂e/m² for commercial offices at RIBA 2025 stage, falling to 350 kgCO₂e/m² by 2030 (RIBA, 2025). The Carbon Leadership Forum (2025) published updated baselines showing that a typical US commercial office averages 450 to 550 kgCO₂e/m² at stages A1 to A5, while best-practice projects achieve 250 to 350 kgCO₂e/m².

Environmental product declarations (EPDs). EPDs are standardised, third-party-verified documents that report the environmental impact of a specific product. The EC3 database maintained by Building Transparency now hosts over 150,000 EPDs globally (Building Transparency, 2025), enabling designers to compare the carbon intensity of concrete mixes, steel sections, insulation products, and cladding systems at procurement stage.

Material substitution hierarchy. The most effective decarbonization strategy follows a hierarchy: first, reduce material quantities through structural optimization; second, substitute high-carbon materials with lower-carbon alternatives (such as ground granulated blast-furnace slag in concrete or recycled steel); third, specify biogenic materials like mass timber or hempcrete that store atmospheric carbon; and fourth, offset residual emissions through verified carbon removal credits.

Digital tools for measurement. Platforms such as One Click LCA, Tally, and the open-source EC3 tool allow design teams to model embodied carbon at concept, detailed design, and procurement stages. One Click LCA (2025) reports that projects using automated LCA tools at concept stage achieve 15 to 25 percent greater reductions than those measuring only at planning submission, because early-stage decisions on structural systems and material palettes drive the largest carbon savings.

What's Working and What Isn't

What is working. Early-stage carbon budgeting is demonstrating measurable impact. Landsec, one of the UK's largest commercial developers, reported achieving 35 percent reductions in upfront embodied carbon across its 2024 development pipeline by setting project-level carbon budgets at RIBA Stage 2 and tracking performance against them through construction (Landsec, 2025). Structural optimization, particularly reducing concrete volumes through post-tensioned slabs, voided slabs, and hybrid timber-steel frames, consistently delivers 20 to 30 percent savings with minimal cost premium. The use of low-carbon concrete mixes containing 50 percent or more supplementary cementitious materials (SCMs) has become mainstream: Holcim (2025) reports that its ECOPact range now accounts for over 25 percent of ready-mix sales in Europe, with carbon reductions of 30 to 100 percent compared with conventional CEM I mixes. Supply chain engagement through EPD-based procurement specifications is also proving effective, with developers reporting that requiring EPDs at tender stage drives suppliers to reformulate products.

What is not working. Data gaps remain a significant barrier. Fewer than 30 percent of construction products globally have published EPDs (Building Transparency, 2025), forcing designers to rely on generic or industry-average data that understates the variation between suppliers. Carbon measurement is often introduced too late in the design process, after structural and material decisions have been locked in. Cost concerns persist, particularly for mass timber in regions without established supply chains, where premiums of 5 to 15 percent over concrete frames have deterred adoption. Greenwashing risks are real: some developers report headline reductions based on cherry-picked baselines or exclude significant emission sources such as MEP systems and fit-out. Verification and assurance of whole-life carbon claims remain inconsistent, with no mandatory third-party audit requirement in most jurisdictions.

Key Players

Established Leaders

• Holcim — Global cement and building materials company with ECOPact low-carbon concrete range available in 25+ markets.
• One Click LCA — Leading whole-life carbon assessment software used on over 50,000 projects worldwide.
• Building Transparency — Non-profit maintaining the EC3 (Embodied Carbon in Construction Calculator) open-access EPD database.
• Landsec — UK REIT with published embodied carbon targets and portfolio-wide tracking since 2022.
• Arup — Global engineering consultancy with deep expertise in structural optimization for embodied carbon reduction.

Emerging Startups

• CarbonCure Technologies — Injects captured CO₂ into concrete during mixing, reducing cement content while improving strength.
• Sublime Systems — Developing electrochemical process to produce low-carbon cement without fossil fuel combustion.
• Material Evolution — Produces alkali-activated cement using industrial waste streams, achieving up to 85 percent lower embodied carbon.
• Tangible — AI-powered platform for real-time embodied carbon tracking during construction procurement.

Key Investors/Funders

• Breakthrough Energy Ventures — Backed Sublime Systems, CarbonCure, and other low-carbon materials startups with over $300 million deployed.
• LETI (London Energy Transformation Initiative) — Industry network publishing open-source embodied carbon guidance that has shaped UK policy.
• World Green Building Council — Coordinates the global Advancing Net Zero campaign with embodied carbon action plans for 30+ national Green Building Councils.

Examples

British Land's 100 Liverpool Street, London. British Land achieved a 45 percent reduction in embodied carbon compared with a conventional steel-and-concrete benchmark on this 520,000 sq ft office redevelopment completed in 2024. The project retained 50 percent of the existing building's structure, used a hybrid steel frame with recycled content above 90 percent, and specified GGBS-rich concrete mixes. The team conducted whole-life carbon assessments at every RIBA stage using One Click LCA, establishing carbon budgets per building element and tracking them against a project-specific baseline. The retention strategy alone saved an estimated 8,500 tonnes of CO₂e compared with full demolition and new-build (British Land, 2025).

Lendlease's Barangaroo South, Sydney. Lendlease set a portfolio-wide target to achieve absolute zero embodied carbon by 2040 and used Barangaroo South as a proving ground. Across the three commercial towers completed between 2016 and 2025, the team progressively reduced embodied carbon by 38 percent per square metre. Key interventions included specifying 60 percent fly ash replacement in concrete, using mass timber for internal cores in later phases, and implementing an EPD-based procurement scorecard that weighted carbon at 20 percent in supplier selection. Lendlease (2025) reported that the cost premium for low-carbon specifications averaged 1.8 percent of total construction cost, offset by reductions in material volumes and reduced exposure to future carbon pricing.

Skanska's Climate Roadmap projects across Scandinavia. Skanska set science-based targets requiring a 50 percent reduction in Scope 3 construction emissions by 2030 from a 2015 baseline. By 2025, the company reported a 32 percent reduction across its Nordic commercial portfolio (Skanska, 2025). The approach centres on a proprietary carbon budgeting tool integrated with BIM workflows, enabling quantity surveyors to model carbon alongside cost at tender stage. Skanska pioneered the use of green concrete with up to 70 percent SCM replacement in structural elements across over 40 projects and partnered with SSAB to pilot fossil-free steel (HYBRIT) in structural connections. The company publishes annual embodied carbon performance data for each project, creating internal benchmarking and accountability.

Hines' T3 timber office series. Hines developed the T3 (Timber, Transit, Technology) office concept, with completed buildings in Minneapolis, Atlanta, and Toronto. The Minneapolis T3 building, using a nail-laminated timber (NLT) structure, achieved 75 percent lower embodied carbon than a comparable concrete-framed building (Hines, 2024). The timber structure stores approximately 3,200 tonnes of biogenic carbon. Hines has since expanded the concept to six additional markets, with each project benchmarked against a concrete baseline to quantify reduction percentages.

Action Checklist

• Set portfolio-level embodied carbon reduction targets aligned with RIBA 2030, LETI, or SBTi benchmarks and disclose progress annually.
• Mandate whole-life carbon assessments at RIBA Stage 2 or equivalent, with carbon budgets by building element that are tracked through construction completion.
• Require EPDs from all structural material suppliers at tender stage and use the EC3 database or equivalent to compare product-level carbon intensity.
• Prioritise structural optimization first, reducing material quantities through efficient design before substituting materials.
• Specify low-carbon concrete mixes with minimum SCM replacement levels (50 percent or above where structurally appropriate) and require third-party verification of mix designs.
• Evaluate mass timber, hybrid steel-timber, and other biogenic structural systems at concept stage, including a cost-benefit analysis that accounts for construction speed, insurance, and fire engineering.
• Integrate embodied carbon metrics into BIM workflows so that carbon is modelled alongside cost and programme at every design iteration.
• Engage supply chains through carbon reduction clauses in subcontracts and by weighting carbon performance in procurement scoring at a minimum of 10 percent.
• Establish third-party verification of embodied carbon claims to avoid greenwashing and build investor confidence.
• Monitor regulatory developments including CSRD, EU Taxonomy, and local planning requirements to stay ahead of mandatory disclosure.

FAQ

How much does reducing embodied carbon add to construction costs? Evidence from completed projects suggests that reductions of 20 to 35 percent are achievable at zero to 2 percent cost premium when structural optimization and low-carbon concrete are prioritised (Lendlease, 2025; Carbon Leadership Forum, 2025). Larger reductions involving mass timber or novel cements may carry premiums of 3 to 8 percent, though these are declining as supply chains scale and carbon pricing internalises the cost of conventional materials.

Which materials have the biggest impact on embodied carbon? Concrete and steel together account for approximately 60 to 70 percent of a typical commercial building's upfront embodied carbon (RIBA, 2025). Concrete volumes are large, and Portland cement clinker is the primary emission source. Steel's impact depends heavily on recycled content: basic oxygen furnace steel carries roughly three times the carbon intensity of electric arc furnace steel. Insulation, cladding, and fit-out materials collectively contribute 15 to 25 percent and should not be overlooked.

What is the difference between operational and embodied carbon? Operational carbon comes from energy consumed during a building's use, including heating, cooling, lighting, and plug loads. Embodied carbon comes from extracting, manufacturing, transporting, installing, maintaining, and disposing of building materials. As grids decarbonise and building energy codes tighten, embodied carbon's share of whole-life emissions is growing. For a new high-performance commercial building, embodied carbon can represent 50 percent or more of total life-cycle emissions over a 60-year reference study period (UNEP, 2024).

Are there mandatory regulations on embodied carbon? As of early 2026, mandatory embodied carbon limits exist in the Netherlands (MPG), Denmark (LCA requirements since 2023), France (RE2020), and parts of Sweden. The UK Greater London Authority requires whole-life carbon assessments for referable planning applications. The EU Level(s) framework provides a voluntary methodology, but the revised EPBD signals future mandatory requirements. California's Buy Clean Act sets maximum global warming potential thresholds for publicly procured structural materials. Momentum is building, and developers should prepare for mandatory limits within the next three to five years across most major markets.

How reliable are embodied carbon calculations? Accuracy depends on data quality. Project-specific EPDs from actual suppliers provide the most reliable figures. Generic or industry-average datasets can understate or overstate emissions by 30 to 50 percent for individual products (Building Transparency, 2025). Using automated LCA tools linked to EPD databases improves consistency, and third-party verification adds assurance. The key is to measure early, measure often, and update calculations as procurement decisions are finalised.

Sources

• UNEP. (2024). 2024 Global Status Report for Buildings and Construction. United Nations Environment Programme.
• World Green Building Council. (2024). Bringing Embodied Carbon Upfront: Coordinated Action for the Building and Construction Sector. WorldGBC.
• RIBA. (2025). RIBA 2030 Climate Challenge: Updated Embodied Carbon Targets for Commercial Buildings. Royal Institute of British Architects.
• Carbon Leadership Forum. (2025). Embodied Carbon Benchmark Study: US Commercial Office Buildings. University of Washington.
• Building Transparency. (2025). EC3 Database Annual Report: EPD Coverage and Data Quality Trends. Building Transparency.
• One Click LCA. (2025). Impact of Early-Stage Carbon Assessment on Reduction Outcomes. One Click LCA.
• Landsec. (2025). Sustainability Report 2024/25: Embodied Carbon Performance. Landsec plc.
• Holcim. (2025). ECOPact Low-Carbon Concrete: Market Adoption and Performance Data. Holcim Group.
• British Land. (2025). 100 Liverpool Street: Whole-Life Carbon Case Study. British Land Company plc.
• Lendlease. (2025). Barangaroo South: Embodied Carbon Reduction Results and Cost Analysis. Lendlease Corporation.
• Skanska. (2025). Climate Roadmap Progress Report: Scope 3 Construction Emissions. Skanska AB.
• Hines. (2024). T3 Timber Office Series: Embodied Carbon Performance Benchmarking. Hines Interests LP.