Assessment of energy impact of ventilation and infiltration of the French regulations for residential buildings.

Ventilation is necessary to insure acceptable indoor air quality as well as to protect the building itself against damage due to condensation Ventilation rates however, must not lead to excessive energy consumption In order to comply with these requirements of hygiene, comfort and energy savings, French regulations stipulate that the ventilation of dwellings has to be general and continuous and achieved by specific systems by which fresh air is provided to the dwellings. The ventilation requirements are expressed by exhaust air flow rates required in each service room as a function of the number of the habitable rooms in the dwelling. Moreover, according to the thermal regulations, the heat loss due to ventilation has to be include in the overall energy loss of the dwelling. For this purpose, calculation rules based on results of numerical simulations has been developed. These rules make it possible to calculate the overall ventilation heat loss : the heat loss due to ventilation system operation and the heat loss due to cross-ventilation. The heat loss due to cross-ventilation depends on air tightness level of the building, ventilation system and meteorological data. This paper reviews the common ventilation systems uscd in France, the various aspects of the French regulations for ventilation of dwellings and calculation rules of vcntilation heat loss. This paper does not cover DCV systems, since they will be dealt in another paper.