What’s the purpose of energy renovation?

4 min


The energy renovation of buildings is THE 21st-century undertaking that will make it possible to reach carbon neutrality. A key issue at stake in the EU’s Green Deal for 2050, it is a major lever in this initiative, delivering concrete solutions to the challenges of the climate emergency, accelerating innovative solutions, reducing energy consumption, and eradicating insecurity.

A genuine climate solution

The opportunities for energy renovation in the European Union are as vast as the territory of its 27 Member States. At present, more than 97% of the buildings inventoried must be modernized to meet energy-efficiency criteria. According to the European Parliament, they account for 40% of the EU’s final energy consumption, 36% of its CO₂ emissions, and 55% of its electricity consumption. The stakes are enormous. So much so that in 2020 the European Commission defined its “renovation wave strategy,” with a view to doubling the annual renovation rate by 2030. As well as reducing emissions, these renovations will improve the quality of life of those living in and using the buildings and are set to create many additional green jobs in the construction sector. In France, the legislative and regulatory arsenal has been expanded since 2015, ranging as far as the Climate and Resilience Act (2021), through which the government is aiming to help reduce greenhouse gas emissions in the building sector — the second-largest emitter after transport.

Controlling our indoor environment has major implications for our health and well-being.

No to demolition; yes to renovation

To launch the sustainable mass roll-out of energy renovation in Europe, several avenues have been prioritized. First, avoiding demolition and rebuilding instead, as demolishing has a carbon cost. Moreover, new builds mean using materials and energy with a high level of embodied carbon. Each square meter built represents 1.5 metric tons of CO₂ equivalent emitted for 50 years. Energy renovation also involves encouraging more private and public stakeholders to renovate by means of a legislative framework favorable to the injection of investment, which would be guaranteed and better targeted, as set out in the NextGenEU plan. Elsewhere in the world, renovation is a must. In the United States, the State of New York thus implemented its ambitious Climate Mobilization Act in 2019 — 50,000 large-sized buildings to be renovated, an €18-billion market by 2030, and the creation of 141,000 local jobs, becoming the sixth American state to adopt a “zero carbon” goal, after Hawaii, California, New Mexico, Nevada, and Washington.

BIM (Building Information Modeling) is a 3D construction project management method.

Reducing operational emissions

Successfully achieving these goals relies on the triptych of energy efficiency, conservation, and decarbonization. To this end, insulation is a starting point primarily concerning a building’s envelope and glass surfaces. This is followed by installing a controlled ventilation system and high-performance heating and air conditioning equipment. All these measures sustainably reduce occupants’ expenses while providing comfort, summer and winter alike. The results can already be seen, with consumption reduced 5.5-fold and CO₂ emissions down 12-fold on average.

Housing nowadays must correspond to a new sedentary lifestyle due, among other things, to working from home and population aging.

But it must be remembered that taking decarbonization action does not do away with the need to wean off fossil fuels. This is in essence the reasoning of the EU, which implemented the REPowerEU plan in 2022 to accelerate its energy independence by 2027. This plan draws on three levers: intensifying efficiency measures, diversifying supply, and massively investing in renewables. However, be warned! Taking the leap to 100% renewables is not enough to achieve high-performance energy renovation. The other major step consists in reducing buildings’ consumption (heating, air conditioning, water, lighting, etc.) by optimizing the running of the renovated building and raising occupants’ awareness regarding its use.

Building renovation is a key sector in improving health conditions in both housing and public and professional buildings.

The question of “well-being” and public health

Reducing consumption is not energy renovation’s sole aim. A broader perspective should be taken, in which housing must correspond to a sedentary lifestyle heightened by population aging and the rise in working from home since the Covid pandemic. In this respect, the French spend an average of 16 hours per day at home[2]. The extent of these phenomena makes housing a key determining factor in health. Yet, 1.6 billion people worldwide live in unfit housing. This substandard housing is often associated with several risks, including economic and energy poverty, insalubrity, disease, etc. The World Health Organization estimates that investing to improve housing conditions would have more positive consequences in terms of health than directly investing in public health. In Toronto, for example, a study of the impact of exposure to fine particles demonstrated that making residential buildings (ventilation, etc.) compliant with the Building Code would allow savings of up to $2.3 billion/year in healthcare costs[3]. In France, the Ministry of Ecological Transition[2] calculates the health and social gain generated by renovating just one of the 1.3 million housing units considered to be the country’s worst “heat-leakers” at €7,500/year on average. Is there still a need to stress the health and economic benefits of building energy renovation? While the issues at stake and solutions are now known, action remains to be taken on a wider scale.

[1] Conserver, adapter, transmettre – Éditions du Pavillon de l’Arsenal, October 2022
[2] “Health and well-being” memo
[3] Impact of residential building regulations on reducing indoor exposures to outdoor PM2.5 in Toronto - Zuraimi, M.S. and Tan, Z, 2015

Photo credits: © Constantin Batyltchouk//stock.adobe.com, © Flamingo Images/Stocksy//stock.adobe.com, © Monty Rakusen/GettyImages, © ninelutsk/stock.adobe.com


In the same format…