In the fight against the impacts of climate change, evolving building codes, performance standards and building practices are being utilized to improve sustainability, resiliency and efficiency—all key components in trying to meet the goals of the Paris Accord and achieve net-zero carbon by 2050. 

But reducing CO2 emissions from the built environment can’t just focus on new construction; retrofitting existing buildings—especially older ones—is an essential component as well. 

The Global Retrofit Index report from 3Keel finds that most countries around the globe have a long way to go to hit the benchmark of the 2.5 percent rate of retrofit by 2030, a target set by the International Energy Association (IEA).

The Global Retrofit Index is a comprehensive report that assesses the progress G20 countries and G7 economies are making to reduce emissions from existing buildings and evaluates the current need for building retrofits, as well as any recent progress and policy commitments. This report showcases the dire need to accelerate the speed and scale of retrofits on a global scale.

Buildings consume nearly half of all the energy produced in the U.S., with the majority sourced from fossil fuels. The industry must face the reality of the large impact that it has on the environment and make further efforts to reduce its energy expenditure.

Buildings are responsible for 37 percent of energy-related carbon emissions (when compared with other sectors): 27 percent from operational carbon (greenhouse gas emissions from energy consumption) and 10% from embodied carbon (greenhouse gas emissions from the manufacturing, transportation, construction, maintenance and disposal of building materials). 

In developed economies, 80 percent of the buildings that will be standing in 2050 have already been built, meaning policymakers must understand the challenges involved in ensuring these buildings are able to contribute to net-zero carbon targets. The Biden Administration has made federal funds available to improve building energy efficiency through the Inflation Reduction Act in 2022, making it clear that action on building energy use is a vital part of achieving these net-zero targets.

Still, the report shows that the U.S. is not on track to achieve its goals with no long-term targets for building emission reductions, retrofit rates or energy efficiency improvements. The need for action in retrofitting is dire, as the U.S. is sitting at 12th in the rankings of G20 countries and tied for last with Japan in the rankings of G7 economies. 

Further showcasing the need to focus on retrofits, the top-ranked countries like Germany and France are not reducing building emissions enough to remain on track to reach the 2050 net-zero carbon targets for the built environment. Currently, fewer than 1% of buildings in major economies are being given energy efficiency retrofit upgrades each year. To get back on track, the industry must achieve the following by 2030: 

  • A 45% reduction in energy consumption
  • A 50% cut in direct emissions 
  • A 60% cut in indirect emissions 


According to the IEA, deep energy retrofits of buildings can reduce energy demand linked to heating by two-thirds or more. Retrofitting 20 percent of buildings in advanced economies over the next five years would reduce CO2 emissions from heating by around one-fifth. 

Despite the lagging rate of retrofits, new technology is making retrofitting more achievable and impactful than ever before. Efforts can include upgrades to HVAC systems, lighting, roofs and switching to cleaner energy sources like solar, wind and renewable natural gas. A retrofit can give older buildings made of brick, stucco or concrete new life, using modern building materials like insulated metal panels, which create an envelope that is more efficient and more impervious to air, water and vapor. 

As Carl Elefante, former president of the American Institute of Architects said, “The greenest building is the one that already exists.” 

To read the full Global Retrofit Index, please visit