The international Active House protocol is an assessment and design guidance tool for the realisation of so-called “active” buildings, able to ensure low energy consumption and at the same time contribute positively to human health, while respecting the environment through the use of renewable energy and sustainable materials. The protocol involves a self-checking procedure of the project, in which design and construction choices are planned in order to provide a general framework with respect to the expected Energy-Comfort-Environment performance. In this context, the purpose of the study is to identify whether in new buildings located in a mountainous environment with a Mediterranean climate and built in compliance with current Italian energy-saving regulations, there are any shortcomings regarding comfort, energy and respect for the environment. It is also intended to identify procedures and design actions necessary to achieve the compliance with the requirements of the protocol, as an implementation of what has already been carried out in common practice. These objectives were achieved by applying the protocol to a newly built school located in the municipality of Alfedena (AQ).