Ahead of the upcoming C40 World Mayors Summit 2019 to be held in Copenhagen, Denmark on October 9-12, 2019, C40 Cities research has released a new report that reveals changes to the construction industry could cut the emissions generated from buildings and infrastructure 44 percent by 2050.

The report, “Building and Infrastructure Consumption Emissions” published by C40 Cities, Arup, and University of Leeds urges action in six key areas to reduce the climate impact of construction in cities:
- Implementing efficiency in material design
- Enhancing existing building utilisation
- Switching high-emission materials to sustainable timber where appropriate
- Using lower-carbon cement
- Reusing building materials and components
- Using low, or zero-emission construction machinery
As well as reducing greenhouse gas (GHG) emissions, the research reveals the additional economic, social and health benefits that ‘clean’ construction could generate. The interventions identified in the research would reduce air and noise pollution, providing health benefits for citizens and the environment.
As the sector responsible for the largest share of consumption-based emissions in C40 cities between now and 2050, it’s clear that the construction sector must do more to reduce its carbon impact. Our research shows that there are significant opportunities to act, but we need to rethink the way buildings and infrastructure are delivered. Making that change a reality will rely on working with all those with responsibility for delivering development. We believe that the construction sector can embrace this change if it invests in the necessary skills and training and seeks to promote innovation. Where this happens, the benefits go beyond emissions reduction – they are social, environmental and economic, cleaner air in cities, less noise, and new job opportunities, said Ben Smith, Energy, and Climate Change Director, ARUP.
They would also spark change within the growing construction economy, providing opportunities for new jobs and skills.
Cities take action on construction to address the climate impact of their consumption
The Scandinavian capitals Copenhagen, Oslo, and Stockholm have pledged to reduce GHG emissions and air pollution from construction sites, in the effort to solve the climate crisis and improve public health.
Raymond Johansen, Governing Mayor of Oslo and Frank Jensen, Lord Mayor of Copenhagen, have both announced their ambition to reduce the use of fossil fuels in construction sites and civil works. The mayors pledged to enact regulations and/or planning policy to ensure they:
- Purchase biofuels and emission-free machinery for the city’s own use
- Demand fossil-and emission-free solutions in public procurement and city-supported projects

In Oslo, all city-owned machinery and municipally-owned construction sites will operate with zero emissions by 2025. Copenhagen’s CPH2025 Climate Plan, roadmap 2017-2020, includes a goal for the City to use fossil-free fuels in its own non-road mobile machinery.
In Oslo, construction sites generate as much as seven percent of total emissions, equivalent to an additional 30 000 petrol cars on the road. New kindergartens, schools, sports halls will in future be built emissions-free and with low climate materials. The building industry is our closest ally and an enthusiastic supporter. We are confident that by 2030 Oslo’s air will be cleaner, emissions lower and environment healthier thanks to the actions we are taking today, said, Raymond Johansen, Governing Mayor of Oslo.
In the budget for 2020 Copenhagen has decided to promote a transformation from fossil fuels to sustainable biofuels, and to fossil-free non-road mobile machinery in its own machines and strengthen efforts that municipally commissioned construction sites and civil work will be fossil-free.
Copenhagen will work to purchase fossil-free fuel for its own machinery and heavy vehicles, pilot projects with tender requirements for fossils-or emission-free construction machinery in construction projects. We will also collaborate with market players to make them use fossil-free fuels, said Frank Jensen, Lord Mayor of Copenhagen, and C40 Vice-Chair.
Holistic approach in Stockholm
Both cities have also pledged to reduce the indirect emissions generated from building works, through the prioritisation of retrofits and refurbishment of their existing stock, de-incentivizing demolitions, and encouraging the use of low-carbon and reusable materials. The Swedish capital Stockholm, on the other hand, is taking a holistic approach to reach the City’s goals to be fossil-fuel-free and climate positive by 2040.

Together with the Swedish Construction Federation and the Swedish Environmental Research Institute IVL, Stockholm has developed a Life-Cycle Analysis (LCA) tool to evaluate all aspects of the building process from a climate point of view – from the choice of materials and the use of machinery to the construction processes. Being now piloted the city aims at using it citywide form 2021.
Together with the building industry and academia Stockholm is creating a powerful tool to scrutinize the climate impact of the whole building process. Using it will help us steer towards the most climate efficient solutions, said Anna König Jerlmyr, Mayor of Stockholm.
One hundred cities represent ten percent of global GHG emissions
All three capitals, Oslo, Copenhagen, and Stockholm also commit to take a leadership role in creating a global market for low-emission construction materials and zero-emission machinery, working through the C40 Clean Construction Forum. Launched in May 2019 in Oslo, the Forum brings together major cities from around the world to use their purchasing power to shift markets within the construction sector.
The world’s cities are growing fast, with an area the size of Milan being built every week. It may be a boom time for builders but the construction industry is a major contributor to the climate crisis. The mayors of Oslo, Copenhagen, and Stockholm recognise that without urgent action to cut emissions generated in the construction of buildings and infrastructure, there is no chance of delivering on the Paris Agreement and preventing catastrophic climate change. As C40’s research demonstrates, citizens will ultimately benefit from cleaner air, quieter streets and lower prices. Now it is up to businesses and industry to recognise the risks of inaction and work with mayors and consumers to make sure everyone benefits from the huge opportunities that lie ahead from clean construction said Mark Watts, Executive Director of C40 Cities.
Consumption-based emissions including construction, as well as food, clothing, aviation, building, and others, from nearly 100 of the world’s big cities already represent 10 percent of global GHG emissions. Without urgent action, those emissions will nearly double by 2050 according to “The Future of Urban Consumption in a 1.5°C World“, another major piece of recently published C40 research with support from Citi Foundation.
Buildings are a cornerstone of our society. We spend over 90 percent of our time in buildings; people rely on them to survive, and they depend on the world’s finite resources to be built and operate. As they are responsible for nearly 40 percent of global carbon emissions, they also represent enormous potential in managing our remaining carbon budget. At World Green Building Council, we are encouraged to see this important research from our partner C40. The opportunities it identifies for cities to address emissions from buildings and construction will support the sector’s critical response to the climate emergency. Through our continued collaboration and World Green Building Council call for coordinated sector action to tackle embodied carbon, we believe there is a future of better and greener buildings for cities all over the world, said Cristina Gamboa, CEO of the World Green Building Council.