Buildings create an intermediate space between occupants and the outdoor environment, with a role of offering a space suitable for the intended activities (e.g. housing, professional work), while fitting into a site. We can break this down into:

• The “indoor environment’’, which constitutes an environment for a building’s occupants. This “built environment’’ must fulfil a number of quality requirements (e.g. functionality of spaces, hygrothermal, visual, acoustic and olfactory comfort, health safety and quality of life);

• The outdoor environment, from the building’s surroundings, the immediate area, and the region (with spatial scales that may vary according to the administrative zoning and an analysis of environmental problems), through to global scale. The aim is to minimize impacts on these different scales (protection of climate, fauna and flora, resources, health and landscape);

• Relations between the indoors and outdoors, which also need to fulfil certain requirements: movement of people and goods, protection, aesthetic quality of the envelope, use of “natural’’ flows (solar energy, rain water), connection to water, energy and transport networks, waste management.