This European Standard describes the methods to calculate the ventilation air flow rates for buildings to be used for energy calculations evaluation, heating and cooling loads. This European Standard applies to buildings with: - Mechanical ventilation systems (mechanical exhaust, mechanical supply or balanced system); - Passive duct ventilation systems for residential and low-rise non-residential buildings; - Combustion appliances; - Windows opening by manual operation; - Kitchens where cooking is for immediate use (including restaurants) This European Standard is applicable to hybrid systems combining mechanical and passive duct ventilation systems in residential and low-rise non-residential buildings. This European Standard applies to buildings smaller than 100 m and rooms where vertical air temperature difference is smaller than 15 K. The results provided by the standard are: ? the air flow rates entering or leaving a ventilation zone; - the air flow rates required to be distributed by the mechanical ventilation system, if present. This European Standard is not applicable to: - Buildings with kitchens where cooking is not for immediate use - Buildings with automatic windows (or openings) - Buildings with industry process ventilation. The definition of ventilation and airtightness requirements (as indoor air quality, heating and cooling, safety, fire protection…) is not covered by this standard. The following information can be found in other standards and technical reports: - guidance to estimate pressure drops in ducts (CR 14378:2002) Table 1 shows the relative position of this standard within the EN EPB package of standards.