7 min
Energy renovation of an apartment

Energy renovation work

Whether you are renovating an old house, a modern house or an apartment, energy renovation is both an economical and eco-responsible option. It encompasses a wide range of operations, such as insulation work, installation of a new heating system, installation of solar panels and renovation of doors and windows. Energy renovation is very much in the news at the moment, as it brings very concrete benefits. The owner can enjoy a regulated temperature in his house, whatever the season. A renovated property is a property that gains value. The details of energy renovation work in this article.

What is energy renovation?

In simple terms, energy renovation is all the work that aims to improve the energy performance of a home. It is one of the best ways to fight against energy poverty. Indeed, houses represent 30% of the energy consumption. Thus, this project aims to :

  • Reduce the heating bill by making the house less energy consuming;
  • Reduce the carbon footprint by releasing lessCO2 into the environment.

In short, it is an ecological and economical gesture.

The public authorities have been trying to encourage this type of renovation since the 1970s. Since then, the French government has put in place regulations to set targets for energy savings. There are two types of renovation work, including the global renovation which allows to reach a more satisfactory performance threshold, and the partial renovation which will be carried out batch by batch.

In order to know the degree of renovation to be carried out in your property, you must find out about the energy performance of your house or apartment. In this case, you can carry out an Energy Performance Diagnosis (DPE), which is not compulsory, but strongly recommended. It will allow you to evaluate your energy consumption, but also its impact on the emission of greenhouse gases. The energy audit is also another solution that goes further than the DPE. It will help you to better define the works to be improved in priority, as well as the points of heat loss to be repaired. 

What work is included in the energy renovation?

Generally, the energy renovation includes 3 types of work all aiming to improve the comfort of the occupants. Insulation, heating and ventilation, these elements aim to increase the energy performance of your homes in a sustainable manner. 

Insulation work

Whether it is thermal, phonic, in the attic, inside or outside, insulation is one of the key points in energy renovation. It aims to limit the entry and exit of cold or hot air in the housing. It must be done in order of priority.

According to the ADEME (Agency for the Environment and Energy Management), 25 to 30% of energy losses in a property come from the roofs and walls. The insulation of attics and roofs must therefore be done first. By doing this, you will reduce your electricity bill by up to 60% and save a lot of energy. Also, a well done insulation will allow you to feel better at home. 

The second action is the insulation of the walls, which represents 20 to 25% of energy loss. It can be done inside (ITI) or outside (ITE). Easy to implement, interior wall insulation consists of lining the existing walls with insulating panels. For the insulation of walls on the outside, it allows to renovate the facade of the house while enveloping them with insulating materials.

With 7-10% of energy loss, low floors are also a priority for energy retrofits. Insulating the lowest floor of your home helps you reduce your heating costs, but also improves the comfort of your feet. Note that this work requires the intervention of a specialist since it is more complex to carry out.

Installation of a heating system

Once your home is well insulated, you can then think about installing a new heating system. This depends greatly on the size of your home and its geographical location. However, with the energy transition, homeowners are turning to environmentally friendly and more economical models. The most popular are:

  • The heat pump (PAC): promotes energy savings, this pump uses renewable energy (water, air, geothermal) to generate heat inside a home;
  • Wood heating: an efficient and economical heating source, it is the least expensive solution, with several options such as the wood stove or the biomass boiler;
  • The solar water heater: it produces no greenhouse gases and uses the sun's energy to provide households with hot water.

There is also the gas or wood pellet condensing boiler which also offers excellent heating comfort. Its role is to generate hot water to redistribute it throughout the heating network (pipes, radiators). Thanks to the evolution of technology, it is now possible to install a regulator or a heating programmer. This maintains the temperature according to the set point adapted to your lifestyle (day/night, week/weekend, vacations). Also, this configuration allows you to save up to 15% of energy.


For an energy renovation to be a success, it is essential to improve the quality of the ambient air in your home. Indeed, in a well insulated house, the outside air penetrates less easily. This is why you must couple your renovation work with ventilation work. The latter ensures the renewal of air and the evacuation of moisture. 

To do so, you can install a Controlled Mechanical Ventilation (CMV) or a Distributed Mechanical Ventilation (DMV). This way, you limit indoor pollution and reduce your electricity bill.

Don't forget to think about the doors and windows. Double- and triple-glazed windows guarantee very good thermal and sound insulation. The installation of shutters also enhances energy conservation in the house or apartment.

What about prices?

Before talking about price, you should know that in the framework of an energy renovation, you must turn to professionals with the RGE certification (Recognized as a guarantor of the environment). This label means that the company you have chosen meets the criteria required by the State to carry out your work. These specialists can be numerous, such as the mason, the roofer-zincer, the facade builder, the waterproofing specialist, the carpenter, the plasterer, the plumber, the heating specialist and many others. They will give you lots of advice, especially on the choice of materials adapted to your renovation.

As far as the amount of energy renovation work is concerned, it depends on quite a few criteria, including :

  • The labor of the professional who will perform the work;
  • The exact condition of the home to be renovated;
  • The different constraints on the place of living ;
  • The materials used and the surface to be insulated;
  • The level and type of energy improvement desired by the owners.

Thus, it is difficult to define the exact price of a home renovation project. However, it is possible to make an average estimate. According to the specialists' opinion, this work costs between 200 euros and 450 euros per square meter. This price can be higher if the house is old. On the other hand, for a less energy-intensive property that envisages a very good energy performance, the price of the renovation will be between 400 euros and 450 euros per square meter.

For routine work, such as attic and roof insulation, the price ranges from 80 euros to 120 euros per square meter. The installation price of a condensing boiler is between 4,000 euros and 8,000 euros (all taxes included). For the heat pump, the average amount depends on the type of installation, including PAC air-air (6,600 euros), PAC air-water (12,700 euros) and geothermal PAC (15,000 euros). As for the ventilation system, prepare an average budget of 900 euros for a VMC and 4 500 euros for a VMR.

What are the possible aids and subsidies for energy renovation?

In order for homeowners to succeed in their energy renovation project, the French government grants financial aid. So, whether you are an owner-occupier, a landlord, a tenant or a free-occupier, there is bound to be a bonus for you.

MyRenovPrime "

MaPrimeRénov' is the central bonus that replaces the Energy Transition Tax Credit (CITE) and the aid from the National Housing Agency (ANAH). It is open to all owners and co-ownerships. The housing concerned is however those built since more than 15 years. This aid is intended to target the most energy-intensive houses and apartments classified as E, F and G in the DPE. The amount obtained from MaPrimeRénov' depends on the household income and the ecological gain from the work. It is paid after the renovation work by bank transfer.

The zero-interest eco-loan

The eco-loan at zero rate (eco-PTZ) is a credit available to all owners wishing to renovate their homes. The amount can be up to 30,000 euros over 15 years, and the interest is paid by the State. All households can therefore benefit from a zero interest rate. To benefit from this scheme, you just need to apply to banks that have signed an agreement with the State. The majority of national banks have concluded this partnership (BNP Paribas, Banque Postale, Crédit Agricole). Homeowners can apply for a zero-interest eco-loan to insulate their home, replace windows or install efficient heating.

The Renovation Advance Loan (RAP)

Offered by the Banque Postale and Crédit Mutuel, the renovation advance loan is intended for low-income households living in thermal flats. It is a complement to financial aid for renovation. However, this device aims to finance the remaining expenses of households that do not have access to conventional loans. Note that the RAP is 75% guaranteed by the State. Regarding the amount of the loan, the rate generally starts at 3,500 euros, the ceiling of which will be determined by the bank.

The energy premium

The energy bonus, also known as the CEE bonus (Certificats d'économies d'énergie), is delivered directly by energy supply companies. It is a financial aid for the energy transition set up to allow individuals to carry out energy saving work at a lower cost. However, this device can only be granted if the insulation work is carried out by an RGE professional. It can be combined with the MaPrimeRénov' aid, the tax credit and the reduced VAT. As for the amounts, they depend on the type of work to be done, the geographical area and the household income.

The Denormandie tax reduction

The Denormandie tax reduction is intended for all individuals who have purchased a home to renovate in a "city center" district. It allows you to benefit from an income tax reduction. The cost of the energy renovation work must represent at least 25% of the price of the property purchased. Note that to apply for this assistance, you must carry out energy efficiency work.

In addition, there are also other financial aids, such as the reduced VAT rate, the energy cheque, the "insulation boost" (attic, low floor, roof) and the "heating boost" (heat pump, boiler, solar water heater), the exemption of the property tax, MaPrimeRénov' Sérénité and many others. Some of these aids can be cumulated, while others can be completed by aids in the form of loans.

What are the benefits of energy retrofitting?

Energy renovations bring only advantages. It is a very profitable investment. These projects improve and enhance the energy efficiency of your home. You can say goodbye to heat loss, drafts and the feeling of cold or heat when you touch the floor or wall. In short, you gain invaluable comfort.

Most renovations also reduce energy consumption. They guarantee long-term energy savings of 25 to 30%. In other words, the cost of the electricity bill decreases, so the most modest households can save a few euros per year. Also, by doing this action with RGE professionals, you will benefit from tailored advice.

In addition to saving energy, renovation is also one of the best ways to preserve the environment. The ecological footprint of housing is reduced, because it favors less energy-consuming equipment. If all buildings are renovated, France will be able to significantly reduce its carbon emissions.

Mathieu Amara

Mathieu Amara

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