Building surge tests climate targets

Global building emissions rose again in 2024, underscoring how rapid urban expansion is outpacing efficiency gains and slowing the sector’s shift towards a net-zero pathway.

Operational emissions from buildings increased 1 per cent to 9.9 gigatonnes of carbon dioxide last year, even as energy intensity improved across parts of the global building stock. The latest Global Status Report for Buildings and Construction 2025-2026, released on 19 May, shows a sector under growing pressure from population growth, housing demand, energy affordability concerns and climate-related risks.

Buildings and construction now account for about 37 per cent of global carbon dioxide emissions, 28 per cent of global energy consumption and nearly half of material extraction. The sector also remains a major economic engine, contributing 11 to 13 per cent of global GDP and employing about 9 per cent of the world’s workforce across construction, renovation, demolition, engineering and related activities.

The report places urbanisation at the centre of the challenge. Global building floor area expanded by 1.7 per cent in 2024 to 273 billion square metres. Each day, the world adds an estimated 12.7 million square metres of new floor space, roughly equivalent to building the city of Paris almost every week. Much of this expansion is concentrated in emerging economies, including India and Southeast Asia, where housing demand, infrastructure growth and rising incomes are reshaping cities.

The figures point to a widening gap between construction growth and decarbonisation. Building energy intensity has fallen 8.5 per cent since 2015, and green building certifications have nearly tripled over the past decade. Yet the pace is still too slow to align the sector with climate goals. Renewable energy supplied only 17.3 per cent of buildings’ energy demand in 2024, leaving heating, cooling, lighting and appliances still heavily dependent on fossil-fuelled power systems in many markets.

Residential buildings dominate the sector’s footprint. They account for 77 per cent of global building floor area and around 70 per cent of buildings’ energy demand, placing housing policy at the centre of climate and affordability debates. Poorly insulated homes and inefficient cooling systems are especially significant in fast-growing cities exposed to heatwaves, where households face rising electricity bills and higher health risks.

“Buildings can either lock in climate risks or deliver safer, healthier, and more affordable living conditions,” said Inger Andersen, executive director of the UN Environment Programme. Her remarks reflect the report’s broader warning that decisions made in the next few years will determine whether new urban development accelerates emissions or helps reduce them.

Finance remains one of the largest bottlenecks. Investment in building energy efficiency reached $275 billion in 2024, bringing cumulative investment since 2015 to $2.3 trillion. But keeping the sector on a net-zero pathway would require energy-efficiency investment to more than double, reaching $5.9 trillion by 2030, or about $592 billion annually. That gap is particularly acute in developing markets, where financing costs, fragmented regulations and informal construction practices often limit adoption of efficient materials and technologies.

Policy progress has been uneven. Building energy codes have been updated in several jurisdictions, including California, Kenya, Japan and Singapore, while green building certification has expanded in China, Colombia, India and Türkiye. National roadmaps are supporting sector transformation in Bangladesh, India, Indonesia, Jordan, Ghana and Senegal. On-site renewable deployment has gained ground in Australia, Germany, India and Pakistan, but the overall transition remains too slow compared with the scale of new construction.

The report also draws attention to embodied emissions, the carbon released through cement, steel, glass, bricks and other building materials before a building is occupied. These emissions are harder to cut because they are embedded in industrial supply chains and procurement systems. Wider use of low-carbon cement, recycled steel, timber where appropriate, circular design and material-efficient construction could reduce the footprint of new development, but these approaches remain unevenly adopted.

Cooling demand is emerging as a defining issue for cities in hot climates. Rising temperatures are increasing the need for air conditioning, while poorly designed buildings can lock households and businesses into decades of high power use. Efficient cooling, passive design, reflective materials, shading, ventilation and district energy systems are becoming central to urban resilience strategies.