Building emissions reach record, challenging global climate goals

Buildings and the materials used to construct them are responsible for about 37 per cent of global carbon emissions. PHOTO: REUTERS

SHARM EL-SHEIKH, Egypt – Carbon emissions from the global building and construction sector hit a record in 2021, adding to the challenges of the world economy reaching net-zero emissions by 2050, according to a report released on Wednesday, on the sidelines of the COP27 climate talks in Egypt.

Buildings and the materials used to construct them are responsible for about 37 per cent of global carbon emissions, making the sector one of the largest sources of mankind’s greenhouse gas pollution that is heating up the planet.

The sector also accounts for more than 34 per cent of global energy demand, according to the Global Alliance for Buildings and Construction (GlobalABC), which wrote the report.

This makes the sector one of the most crucial in tackling climate change. Key measures include making buildings far more efficient and using low-carbon construction materials. These steps are all the more urgent as more people move to cities and as the global population is forecast to reach more than nine billion by 2050.

In Singapore, buildings make up more than 20 per cent of the Republic’s carbon emissions and the sector is a major focus of government and corporate efforts to go green. 

GlobalABC’s report is an annual snapshot of the world’s building and construction industry. It found that the sector’s 2021 operational energy-related carbon dioxide emissions were up 5 per cent from 2020 and 2 per cent higher than the pre-pandemic peak in 2019.

Operational energy use covers things such as heating, cooling, lighting and equipment, including pumps and generators. Operational emissions reached a total of 10 billion tonnes of CO2-equivalent – more than twice the annual CO2 emissions of the United States, the world’s No. 2 carbon polluter after China.

In addition, estimated CO2emissions from producing building materials such as concrete, steel, aluminium and glass totalled a further 3.6 billion tonnes.

In 2021, investments in building energy efficiency increased by 16 per cent to US$237 billion (S$332.3 billion), but growth in floor space outpaced efficiency efforts, the report found.

The findings mean the gap between the climate performance of the sector and the pathway to decarbonising by 2050 is widening.

“Years of warnings about the impacts of climate change have become a reality,” said Ms Inger Andersen, executive director of the United Nations Environment Programme, which hosts GlobalABC.

“If we do not rapidly cut emissions in line with the Paris Agreement, we will be in deeper trouble.”

To get a sense of the scale of growth in the sector, the report said the increase in global gross floor area between 2015 and 2021 is equivalent to the total land area covered by buildings in Germany, France, Italy and the Netherlands. If it were built on one level, it would total about 24,000 sq km – about 33 times the size of Singapore.

GlobalABC – which has 256 members, including 37 countries, and business, civil society and intergovernmental agencies – says the equivalent of Paris is added in floor space every five days, and the equivalent of Japan every year. Half of the buildings that will be standing in 2060 have not yet been built, it says on its website.

Huge growth is expected in Africa and Asia, especially in China, where building materials are the third-largest emitter after power and steel.

In a further blow, China recently set 2030 as the date for peaking carbon emissions for building materials, such as cement. This is much later than the 2023 date that the cement industry proposed in September. The building materials sector as a whole had aimed to peak by 2025, Bloomberg reported on Wednesday.

The report recommended boosting energy efficiency investments and issuing mandatory building energy codes. Between 2015 and 2021, the number of countries with building energy codes rose from 62 to 79, the report said. However, only 26 per cent of countries have mandatory building energy codes for the entire sector.

Ms Andersen said another solution is rethinking construction materials, particularly since raw resource use is predicted to double by 2060. “The sector can reduce its impact by looking at alternative materials and decarbonising cement.”

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