With the transposition of the European Red III directive, the rules change for those who build or renovate a property: here are the interventions that are involved, the percentages to be respected, the systems allowed, the exceptions and what happens if you don’t comply
There is one more item on the to-do list for those who plan to renovate their home from now on. From the August 3, 2026 in fact, the rules on the use of renewable energy in buildings are changing, as a result of the provision with which Italy implemented the European directive Red III. From this date, the obligation to install systems powered by renewable sources will no longer only concern those who build a building from scratch, but also those who renovate, in some cases.
What changes from August 3rd for those who renovate their homes
The principle behind the European directive is simple: buildings must no longer just be places that consume energy to heat, cool or produce hot water, but must themselves contribute to producing a share of it from clean sources. In practice, starting from 3 August 2026, anyone presenting a significant new construction or renovation project will have to demonstrate, through the technical report required by law, that they can cover a certain portion of their energy needs with renewable source systems. These are not small ordinary maintenance works, but interventions that significantly modify the structure or systems of the property, including new public buildings. The news is that the obligation will no longer only concern new buildings or the most invasive renovations, but also those who simply replace the heating system, for example by changing an old gas boiler.
The percentages to be respected with the new European Red III directive
The minimum quotas of renewable energy required change based on the type of intervention. For them new private buildings at least 60% of the energy for air conditioning and hot water must come from renewable sources and for new public buildings the threshold rises to 65%. For them first level renovations (works that involve more than 50% of the building’s dispersing surface and also include the renovation of the heating system) the required share is 40%. Finally, for the second level renovations (interventions on a surface greater than 25%) e replacement of the heating system: the minimum quota drops to 15%, calculated only on air conditioning consumption, without considering domestic hot water. These are percentages that must be considered already in the design phase, because they represent a necessary requirement to obtain the building permit. The thresholds will be updated periodically, at least every five years.
Which systems can be installed from August 3rd to renovate your home
European legislation does not impose a single technology, you can choose between different options. They can be installed i photovoltaic panelsfor the production of electricity; The solar thermalto generate domestic hot water by exploiting the heat of the sun; the heat pumpsincreasingly used to replace old gas boilers or boilers geothermal systemswhich exploit the natural heat of the subsoil. And those who switch from a gas or LPG system to a pellet generator for boilers will have to respect stricter limits on particulate emissions.
Sanctions and exemptions: what happens to those who do not comply with the European directive from 3 August
Without a project that respects the obligations on renewables, the consequence is the suspension of the authorization for the works by the Municipality. However, there are some ways out. The obligation can be excluded or reduced when a qualified technician certifies, in the technical report, thetechnical impossibility to install the required systems, for example due to landscape, architectural or space constraints. Or it proves itself not economic convenience of the intervention compared to the benefits obtainable. In these cases the decree allows the application of alternative requirements linked to the consumption of non-renewable primary energy, but these are exceptions that must be carefully justified and documented, not automatic shortcuts.
