The energy needs of buildings account for 40 per cent of the total energy demand in the European context and are to date mainly met by traditional technologies using fossil fuels. In order to complete projects to reduce climate-altering emissions, Europe imposes increasingly stringent constraints on new buildings or those subject to major renovation, but at the same time it is necessary to upgrade the existing building stock in order to achieve the targets necessary to keep the global temperature below the 1.5 °C increase compared to 1990. This paper investigates the use in the civil sector of hydrogen as a new sustainable energy vector, analyzing the ways in which it can contribute to the decarbonization of energy supply, in line with the predictions formulated by IRENA.