Why the building sector’s emissions milestone requires data-driven reinforcement


New findings from the UN’s Global Status Report for Buildings and Construction reveal that built environment sector emissions did not rise in 2023 – despite global construction continuing to expand. On the surface, this may sound like an encouraging development – one that shows actions to decarbonize the sector are heading in the right direction. But take a closer look at the findings, and it’s clear we still have a long way to go.

The latest figures indicate that buildings still consume a staggering 32% of global energy and contribute 34% of global CO₂ emissions, with operational emissions alone reaching a record 9.8 gigatonnes in 2023. Rather than a sudden conclusion to climate efforts, this report should serve as a pivotal call to action; one that galvanizes further commitment to innovative solutions for net-zero buildings. This pathway must encompass a whole building life cycle approach, where every phase – from design and material selection to construction and operation – contributes to the sector’s march towards net-zero carbon.

Stabilizing emissions, while significant, is only half the story. While energy intensity from buildings has declined from 146 kWh/m² in 2015 to 132.2 kWh/m² in 2023, this remains far from the targeted reduction to 119.4 kWh/m² that is required to meet the goals set by the Paris Agreement. Furthermore, total energy-related emissions from the buildings sector actually rose from 9.3 gigatonnes CO2/year to 9.8 gigatonnes CO2/year – significantly lagging behind the necessary reduction target of 6.7 gigatonnes CO2/year.

The built environment must move swiftly from maintaining current levels to driving down emissions across a rapidly expanding global construction footprint. The technologies to support this shift already exist and as the saying goes, knowledge is power. Sophisticated energy modelling and simulation can pinpoint inefficiencies before ground is broken or a single retrofit or new construction project begins. By evaluating environmental impacts from inception, through operation to repurposing, developers, building owners and operators can avoid locking in decades of avoidable emissions and resource waste, and ensure their buildings perform optimally over time.

This need for data-driven insight becomes more urgent with each new project – but also when it comes to optimizing existing buildings, particularly as the architecture, engineering and construction (AEC) sector strives to meet net-zero targets at scale. Urban centres and populations are rising; while demand for construction surges, developers risk locking in decades of sub-optimal performance if they fail to think long-term. It’s firmly in their interest to adopt a whole-systems approach, taking a holistic view of the many factors that can impact a building’s performance across its lifetime.

Rigorous, physics-based analysis not only helps to optimize performance at the individual building level, but can also reveal how varying energy demands might be balanced across multiple properties – optimizing solar generation, shared storage and even local energy trading. This collaborative strategy not only reduces operational costs and enhances occupant comfort, but also safeguards the planet for generations to come.

The Global Status Report for Buildings and Construction identifies key strategies like retrofitting older buildings, enforcing more stringent building energy codes, and reducing embodied carbon in materials such as steel and cement to support further progress. Successful implementation, however, hinges on harnessing the power of accurate, real-time data and simulation to ensure that solutions are not just well-intentioned, but genuinely effective.

These measures have the most impact when pursued through a holistic lens. Advanced simulation platforms can replicate real-world building conditions to test the outcome of multiple scenarios, from early-stage design decisions to operational energy use and even end-of-life outcomes. Such insights enable building owners and policy-makers alike to prioritize interventions, direct investments wisely, and track measurable outcomes. In this way, data is the lynchpin for accelerating climate-friendly interventions and practices across the sector – yielding verifiable reductions in both embodied and operational emissions.

A whole life cycle-centred strategy means going beyond short-term fixes. By incorporating entire life-cycle assessment from the earliest planning phases through to operation, we can select lower-carbon materials, incorporate renewable energy, optimize operational strategies and ensure that buildings are future-proofed against potential climate scenarios and changes in use. This approach not only drives down immediate emissions but also safeguards against unintended consequences, such as the need for costly retrofits or carbon-intensive demolition further down the line.

That being said, we shouldn’t lose sight of the fact that this year’s report offers a rare sign of optimism. It shows that forward-thinking policies, innovative financial models and emerging technologies can work together to stabilize emissions – they just aren’t being implemented with the scale and urgency that is required. The ultimate goal remains ambitious. Beyond new builds, existing structures must be retrofitted and upgraded, materials rethought, and financial instruments refined to incentivize deep sustainability. AEC professionals, building owners and operators have a big responsibility to act on the opportunity and deliver tangible change.

Supporting this trajectory will involve all stakeholders aligning in an ethos of continuous improvement and data-driven accountability. And it’s not just design and operations teams who should care. For many chief financial officers, for example, a whole building life cycle approach delivers strong business benefits: Reduced operating costs over the long-term often allow retrofitting initiatives to pay for themselves, meaning organizations may not even require external funding. Investors also stand to gain: Once the financial returns become apparent, up-front costs are often outweighed by the long-term savings and potential dividends.

Green bonds, tailored loans and other innovative funding models can supercharge retrofitting efforts, providing the capital needed to modernize ageing building stock. Meanwhile, advanced simulation and continuous performance monitoring ensure that design intentions hold true throughout a building’s operational life. With data illuminating every step, the built environment can shift from a primary emissions culprit to a core driver of climate resilience.

While the 2023 plateau in emissions marks an encouraging moment, the true test will be how rapidly we can convert a standstill into a swift reduction. By tapping into robust modelling technologies, sharing learnings industry-wide, and pushing for stronger policy frameworks and investment, the built environment sector can move decisively towards a net-zero future. The industry is on the cusp of transformation – it must now choose to seize the moment.