Since June 2013, an energy efficiency certificate has been mandatory for the sale or rental of any property, according to Royal Decree 235/2013. This Royal Decree approves the basic procedure for energy certification of both new and existing buildings. It is important to know that in addition to having an energy efficiency certificate, it must be registered with the competent authority of the Autonomous Community.
The energy certificate is valid for five years, from the date it is registered with the Competent Authority of each Autonomous Community. When work is carried out on an apartment with a valid energy efficiency certificate that affects the building envelope or the system, the certificate must be updated if you plan to sell or rent the property.