Insulation: the cornerstone of your energy renovation

Today, owners are looking for lasting solutions to meet the timetable of obligations, but also to enhance the value of their property assets, reduce bills and ensure thermal comfort for future buyers or tenants.

Why start the energy renovation of your property?

The 2021 Climate and Resilience Act tightens the regulatory framework and seeks to remove energy sieves from the French housing stock.

By accelerating the transition towards more efficient homes, renovation works are becoming an obligation for certain properties.

Improving thermal comfort and saving energy

When owners decide to start energy renovation works, it is above all to save energy and provide better thermal comfort in the home.

In this case, insulation is the most cost-effective investment! It is the first change to make to your property!

Indeed, poor insulation leads to considerable heat loss:

• Up to 30% through the roof,
• 25% through the walls,
• 15% through the windows,
• 10% through the floors.

The principle of carrying out energy renovation works starting with insulation: heat less but heat better!

Insulation is the envelope of your building and helps to keep the heat in during winter and the cool in during summer.

Meeting regulatory obligations

Energy renovation works are above all a way of getting ahead of the reforms introduced by the 2021 Climate and Resilience Act. This act imposes strict constraints on the sale and letting of your property.

Since 1^st January 2025, homes rated G on the EPC have been banned from letting, and this ban will extend to homes rated F in 2028 and then E in 2034. These measures are being introduced above all to remove energy sieves from the French housing stock.

Insulation and energy performance: the role of the EPC and the energy audit

Poor energy performance in your home can mean a significant reduction in its value. To prevent your property from losing value on the market, start its renovation now and carry out an EPC and/or an energy audit.

The Energy Performance Certificate: the starting point

The EPC is something of a compass for energy renovation! It is mandatory for any property transaction (sale or letting) and makes it possible to assess the home’s energy consumption and its greenhouse gas emissions.

The result of this assessment? Two labels that classify your home with a rating ranging from A (very energy-efficient homes) to G (very energy-hungry homes, energy sieves).

The energy audit: the essential tool for prioritising your energy renovation

Although the EPC is the gateway to energy renovation, the energy audit goes much further. It is a genuine roadmap that will guide you by proposing works scenarios that are prioritised, ranked and costed.

By going further in studying the building and precisely identifying the areas of heat loss, you are given a personalised proposal. Three scenarios may be put to you:

• A step-by-step scenario, stating the energy class gain at each stage,
• A whole-house renovation scenario, with the final gain,
• A scenario taking into account the quotes already obtained by the owner.

Carrying out an energy audit during a renovation project means being able to benefit from financial support, but above all sound advice!

When should you carry out an energy audit?

Since 1^st April 2023, the energy audit has been mandatory when selling detached houses and single-ownership buildings rated F or G. As with the EPC, a timetable has been drawn up, and this obligation has extended to homes rated E since 2025 and will concern homes with an energy rating of D from 2034.

The energy audit identifies insulation priorities

The energy audit generally highlights a fundamental rule for your energy renovation works: always start with insulation before changing your equipment or joinery.

Indeed, changing your windows or replacing your ageing heating system with a heat pump, for example, are good moves! But in a poorly insulated home, it is like filling a leaky jug.

The energy audit makes it possible to identify works priorities and, in particular, the order in which to insulate your home. As we mentioned, heat losses are not equal, whether they occur through the roof or the joinery.

For even more convincing results, it is important to install an effective ventilation system, which will help avoid any damp problems in a home that is now airtight.

The importance of energy performance in property transactions

The value of a coherent energy renovation

A successful energy renovation means betting on a comprehensive and coherent approach.

Avoid common mistakes by surrounding yourself with experienced and certified professionals who will provide all the help you need and ensure the works are effective.

Common mistakes when renovating your home

We mentioned it briefly, but one of the most common mistakes when carrying out an energy renovation is changing your heating system without first having insulated your home.

The result? Equipment that is meant to bring you many benefits, which you will see go to waste because of heat loss. The power of this equipment generally does not make up for these “leaks” caused by poor insulation.

Another common trap, stemming from a very widespread misconception: changing your windows can gain you one or two classes on your EPC rating! Here again, insulation is the key! While changing windows does contribute, it is not necessarily the biggest source of heat loss in your property.

Finally, another common mistake: not carrying out coordinated works. This approach can prevent you from benefiting from the combination of the different works carried out, and can sometimes even complicate your access to certain financial support for whole-house renovations.

The financial support available to fund your energy renovation works

As we mentioned just before: when you start a whole-house energy renovation of your property, financial support is available to help with your project. Here are a few:

• MaPrimeRénov’ to support the energy renovation of your home under certain conditions,
• The éco-PTZ, which lets you borrow interest-free to carry out your renovation works. This support can be combined with MaPrimeRénov’, sometimes making it possible to fund your entire project,
• Energy Savings Certificates (CEE), which are paid by energy suppliers to add a top-up to your funding.

The carbon calculator: the new tool for optimising your insulation

There’s something new in the field of energy! We now talk in particular about embodied energy. What’s that? It is the amount of energy consumed over the entire life cycle of a material, from extraction through to installation and recycling.

One tool in particular has recently been developed: the carbon calculator. It makes it possible to assess the carbon impact of the various insulation solutions. It is now possible to favour higher-performing insulation with a low environmental impact thanks to this tool.

Beyond an environmental criterion that is becoming increasingly important for many buyers, the carbon footprint of materials is already starting to influence future regulations: the RE2020 (2020 Environmental Regulations) now introduces the calculation of the carbon footprint over the entire life cycle of materials, and the thresholds are evolving.

Insulation and regulatory obligations: where do we stand?

A quick recap of the regulatory obligations concerning insulation, but above all the energy renovation of your home.

Regarding letting:

• Letting banned for G-rated homes since 2025,
• Letting banned for F-rated homes in 2028,
• Letting banned for E-rated homes in 2034,

Regarding sale:

• The energy audit must be given to potential buyers from the very first viewing,
• It is valid for 5 years,
• It is mandatory for homes rated F, G and E,
• It will become mandatory for homes rated D in 2034,

These regulatory obligations are above all a means of bringing about the energy transition! Get ahead of these constraints now and avoid finding yourself stuck during your property transactions!

Our consultancy helps you carry out insulation that makes sense!

Insulation is a strategic as well as a regulatory investment in your property. Improving your insulation means enjoying and being able to offer better thermal comfort, being able to save energy, and complying with the legal framework!

RITMODiag supports you in carrying out EPCs and energy audits for your home. Take advantage of the services of experienced surveyors to optimise your renovation project!