Building sector must play its part in reducing CO2 emissions

Much more serious consideration must be given to cutting whole-life CO2 emissions of buildings – from the production and transport of materials to the disposal of old properties – if the construction industry’s carbon footprint is to be substantially reduced, University of Manchester academics have warned.

In an article based on research conducted in partnership with the University of Melbourne, Judy Too and Obuks Ejohwomu reveal that the building sector is the single largest contributor to greenhouse gas emissions, accounting for 40% of global emissions, with the UK building sector responsible for approximately 25% of domestic emissions.

They write: “At a tipping point for global action on climate change, this is truly building a house on sand.”

In their piece, published by the University’s policy engagement unit Policy@Manchester, Ms Too and Dr Ejohwomu propose three areas where policymakers can take positive action to reduce emissions in buildings.

First, they argue that manufacturers should be mandated to produce Environmental Product Declarations (EPDs) for all materials, adding: “This will build the necessary knowledge infrastructure, while increasing awareness of the embodied carbon content of building materials.”  Acknowledging that the market may not yet be properly prepared to meet the necessary requirements “due to significant gaps in primary data,” they suggest a series of graduated steps including the short-term use of industry wide EPDs with product specific EPDs becoming mandatory within two years.

Second, based on their research, the University of Manchester academics believe that end-of-life treatment of materials and buildings is often overlooked.  They advocate the update of building code regulations to include considerations for whole-life carbon impacts.  Ms Too and Dr Ejohwomu write: “This update will mandate whole-building Life Cycle Assessment, shifting the focus from prescriptive emission limits to evaluating and optimising the overall performance of the building in terms of its environmental impact.”

Third, they argue for the introduction of “project-level carbon budgets based on predefined boundaries and benchmarks aligned with sectoral carbon limits” with a target time of three to five years.  They explain: “These limits establish precise emission targets that building projects must meet, with enforcement mechanisms such as audits and monitoring systems in place to ensure compliance. By implementing such limits, projects are held accountable for their emission levels over the building’s lifecycle, thereby driving carbon reduction within the building sector.”

Summing up how their research can enable the building sector to reduce CO2 emissions, Ms Too and Dr Ejohwomu conclude: “By acting on these recommendations, policymakers can lead a combined effort to balance environmental goals with economic considerations.  To not do so and continue to ignore the whole-life emissions of buildings risks locking-in unsustainable buildings for decades.”

Built on sand: the need for new environmental standards in the construction industry is available to read on the Policy@Manchester website.