Ventilation systems in residential buildings: requirements to the design of systems and equipment.

Evaluates results of the 'Ventilation in Residential Buildings' research programme of the German Federal Ministry for Research and Technology. It was found that conventional ventilation methods based on infiltration and window opening cannot secure proper air quality and at the same time provide energy conservation and user comfort, nor can intelligent ventilation habits be expected of the average user, for subjective and objective reasons. All ventilation systems evaluated had shortcomings. Soft displacement ventilation techniques taking advantage of natural buoyancy forces instead of contaminant dilution can be expected to provide major improvements in ventilation efficiency and user comfort in future.