The study takes into account 750 office buildings and over 2,000 villas. The lowest costs per square meter for air conditioning during summer incurs in green buildings, while old villas have the highest expenses.


In 2015, cooling offices for employees in the months of high heat cost between EUR 120 / month for a space of 100 square meters, located in a villa, and up to EUR 9000-12000 / month for an office space of 10,000 square meters located in a class A office building.


Types of air conditioning systems used in office premises:

- In class A and B + buildings – four pipes centralized system

- In class B, C buildings and some new/recently refurbished villas – two pipes centralized systems

- In some class C buildings and villas – split systems (with external units on the walls)


The two pipes systems offer only alternative hot or cold air (warm air in winter or cool air in summer) and does not allow employees who have different comfort temperatures (like those from different countries, many among multinationals) the option to have both cooling and heating in a given moment.


The four pipes system gives users the freedom to use both hot air and cold air in a building. In such a building, employees in offices located on the north facade of the building can use the heating option (in a season of transition for example), while the south facade can use, at the same time, cool air. (source: