A method for operating an installation for the automated control of the conditions in a building, the installation including a central control unit, electrical equipment items with which areas of the building are equipped and a unit for managing sensor(s) suitable for measuring an input physical quantity, includes modelling the building and the building areas, obtaining at least one first value of the input physical quantity measured by the sensor(s), iteratively determining values of at least one output physical quantity, as a function of at least one second value of the input physical quantity, of the model of the building and of the areas of the building, and using the determined values in order to control the electrical equipment items.