The construction sector "slows down" its decarbonization, warns the UN

BarcelonaThe construction sector worldwide is slowing down its decarbonization despite "positive changes" made since 2015. "Progress has slowed," warns the tenth Global Status Report for Buildings and Construction, prepared by the United Nations Environment Programme (UNEP) and the Global Alliance for Buildings and Construction (Global ABC). It establishes construction as a "cornerstone" of human life, both economically and climatically.

On the one hand, construction accounts for between 11% and 13% of the global GDP and employs 9% of the workforce. On the other hand, it is responsible for 37% of CO₂ emissions and 28% of energy consumption. Every week, the equivalent of the entire city of Paris is built worldwide. In 2024, the total built area expanded by 273 billion square meters, an increase of 1.7%.

"The built area worldwide has grown rapidly, while energy demand and emissions have advanced more slowly," points out Martin Krause, director of the United Nations' Climate Change division. "In other words: energy efficiency, clean energy, and design improvements are yielding tangible results; this is positive. However, what we need is speed and scale," he summarizes.

A "significant" gap

Since 2015, the energy intensity of buildings –defined as annual consumption relative to their area– has decreased by 8.5% and the use of renewables has grown by 4.7%. Despite the improvements, the sector is far from what is needed to meet the objectives of the Paris Agreement. "There is a significant decarbonization gap, of 49 points, compared to the trajectory we should be following," laments the lead author of the study and executive director of the Buildings Performance Institute Europe, Oliver Rapf.

In geographical terms, progress is uneven. Europe is the only region that reduced the energy consumption of buildings since 2010 (18% less), while in the Middle East (49%), Sub-Saharan Africa (37%) and Asia (27%) it increased the most. "European Union policies have an effect," emphasizes Rapf, referring to the club's initiatives to mitigate the effects of climate change.

Homework for governments

The report highlights the positive impact of green certification "with standards aligned towards zero emissions", calls for them to be given greater prominence and demands that governments have the capacity to ensure compliance and sanction infringements. Energy efficiency standards cover approximately 60% of new construction worldwide, but their application is "scarce" in countries where building growth is greatest.

Climate advisor Hanane Hafraoui calls for "public procurement to be understood in a much more strategic way". "Governments don't just buy buildings, they also create demand for low-carbon solutions", she reflects. She urges states to "provide long-term regulatory certainty" and to issue "clear signals" as the future lies in resilient, low-emission buildings.

Housing crisis

Krause maintains that "buildings are a central part of the climate problem, but also of the solution." He goes beyond the environmental challenge and places them at the center of the debate, in a context of global uncertainty marked by the instability of energy markets and the housing access crisis.

"When buildings are well designed, they can cut bills, reduce energy pressure, and improve safety almost immediately. As heatwaves become more intense and more frequent, for example, buildings become the first line of defense," stresses Krause. In turn, Hafraoui insists: "We must address the housing and climate crisis together."