Ahead of the first UN-led buildings and climate summit, Arup and the World Business Council for Sustainable Development (WBCSD) are calling for urgent action to consistently measure the carbon footprint of buildings.

This move is essential to cutting carbon in one of the most polluting sectors of the economy – with the built environment responsible for 37%* of global emissions, greater than transportation at 25%.** It is estimated that less than 1% of building projects currently calculate and report their full carbon footprint, with net zero buildings still a novelty.***

Arup and the WBCSD warn that without understanding exactly where carbon comes from in buildings, it will be impossible to make the scale of cuts needed to meet the Paris Agreement to hold global average temperature rises well under 1.5°C.

The summit, co-organised by the UN and French Government, follows the launch of the 2030 Buildings Breakthrough Agenda at COP28, which aims to make near-zero emissions and climate resilient buildings the new normal by 2030.**** Representatives from more than 40 governments, and the European Commission, will join key players from the construction sector in Paris on 7-8 of March to drive forward building decarbonisation.

At the summit, Arup and the WBCSD are calling on global property, construction and building design leaders to work together to standardise the collection and sharing of carbon emissions data for buildings. Developing an international data ecosystem is essential if the global building supply chain is to learn the most effective ways of driving down emissions.

Arup has been ambitious in its own work to standardise whole-life carbon (WLC) data across its global portfolio of buildings. It has developed an international dataset assessing its global building design project portfolio using WLC techniques, which includes over 1400 buildings projects across more than fifty countries, using its digital platform Zero.

The challenges faced by the firm in global WLC data collection and the insights gained so far will be shared with the wider industry at the summit in a new case study being issued: Whole Life Carbon Assessments at a Global Scale. Key takeaways include:

  1. Different building functions – for example a data centre compared to a residential building – can vary up to a factor of 10x in the amount of carbon emissions they generate. Specific data is needed on function, size, and location to be able to prioritise affordable decisions on carbon reduction.
  2. Carbon emissions rise substantially from planning stage to the building being used. Greater scrutiny of carbon emissions all the way through buildings projects needed to combat this.
  3. Energy efficiency improvements and grid decarbonisation alone will not be sufficient to halve emissions by 2030, reducing embodied emissions is essential.
  4. Reducing embodied carbon emissions in supply chains is the vital next step to reaching embodied carbon reductions of 40% by 2030.

Nigel Tonks, building decarbonisation expert at Arup, said: “You can’t manage what you don’t measure. Paris is the first time our industry has come together with national governments from all over the world, to tackle its impact on climate. Standardising carbon measurement and reporting will make wide scale adoption of whole life carbon measurement much easier.

“It will improve the insights we can draw from data to give property asset owners, investors, and developers the best advice they need to make the right decisions that lead to halving emissions across new and refurbished buildings. Unless the buildings sector is made a priority for decarbonisation, we will fail to keep temperature change under 1.5°C.”

Work from the WBCSD and Arup has previously shown that as much as 50% of the entire carbon emissions of a building come from embodied carbon – the manufacture of materials and the construction process – rather than from the operation of the buildings. It also found that typically as few as six materials, such as steel and concrete, account for 70% of the construction-related embodied carbon.***

At the forum in Paris, Arup will continue to demonstrate its active leadership in WBCSD’s Built Environment Market Transformation Action Agenda, which calls for wide scale adoption of WLC assessments, integrating carbon cost in product pricing, and transforming incentives towards low-carbon solutions.


UN Environment Programme: 2022 Global Status Report for Buildings and Construction
** Our World in Data: Emissions from Transport
*** Arup & WBCSD: Net Zero Buildings, where do we stand?
**** The Buildings Breakthrough, UNEP 

What they say

Arup’s own journey to a standardized WLC data collection across its global portfolio is a significant case for what is needed at industry level. We encourage companies to build on these learnings and challenges, and call on all actors in the industry to join our efforts in driving harmonization in whole-life carbon accounting through a globally consistent and transparent approach.

Roland Hunziker

Director for Built Environment at the WBCSD