The world needs to achieve net zero by 2050 if we’re to avoid the catastrophic impacts of warming above 1.5⁰C.
Heat leaking from our buildings could be a critical roadblock. A study from BPIE shows that improving wall and roof insulation could reduce the energy demand of homes in selected EU member states by 45%. As the weather turns colder, consumers in poorly insulated homes — already facing energy bills at record highs — could be heating their homes more than necessary.
More efficient buildings
Inefficiencies must be tackled to reduce emissions from one of the world’s biggest culprits: the built environment. Buildings are responsible for 37% of energy-related carbon emissions, globally: 27% from heating or cooling our buildings and their consumption of electricity; and 10% from emissions during construction and maintenance, according to the UN Environment Programme.
We must transform the way buildings use energy by making them more efficient. This can only be done by retrofitting the world’s existing building stock so it consumes less energy.
Targets still unmet
According to the International Energy Agency (IEA), 20% of buildings need to have a deep retrofit before 2030 for any chance of meeting targets under the Paris Agreement. However, the findings of the Global Retrofit Index — a new report from sustainability consultancy 3Keel with the support of Kingspan, the global leader in insulation — have found that the sector is nowhere near on track.
Judging by the activity of the G20 nations, none of the world’s major economies are doing enough to decarbonise their built environments in line with global net-zero targets.
No country in the study (of G20 countries that publish sufficient data, as well as two other European nations with notable retrofit policies) scored well across all the criteria. Even the best-performing European countries have a long way to go to meet the IEA’s target retrofit rate of at least 2.5% per year by 2030. Among G20 nations, Germany leads the way, followed by France. Among the G7 members, Canada, USA and Japan ranked lowest.
Utilising existing tools
The sector’s energy intensity — energy used per meter of floor space — needs to drop five times more quickly this decade than it did between 2015 and 2020 with a 45% reduction in energy consumed per square meter by 2030. This can only be done through a 50% cut in direct emissions and a 60% cut in indirect emissions, according to the IEA.
This may seem a Herculean task, but the tools and strategies already exist. In the French town of Hem, a housing development has trialled an innovative retrofit model called EnergieSprong. By using low-cost, established technologies including thermal insulation, triple glazing, modern heating systems and prefabricated facades, the movement demonstrates a way to create net zero homes affordably. The cost is generally paid over 30 years by halving household energy bills.
This is just one of the tools and approaches the construction industry has developed to increase the retrofit rates to the IEA’s 2.5% annual target.
Global efforts
While the Global Retrofit Index does not list a single country with sufficient retrofit policies in place, it does identify areas of best practice, including the UK Government’s plan to phase out new gas boilers in existing residential properties by 2035 and similar ambitions to introduce heat pumps in commercial and public buildings.
In Australia, 30% of homes have a solar photovoltaic system — with the majority installed over the past five years, demonstrating the potential scale of change. California draws praise for its ambitious standards to make all new homes electric-ready while encouraging rooftop solar systems and heat pumps.
Today, a standard retrofit only reduces energy intensity by less than 15%, but around the world, there are examples of how to improve this and make buildings fit for a net zero future. By examining the progress of the world’s largest economies, governments can benchmark their progress and get to net zero faster.