Natural ventilation through cracks, or should cracks be sealed. Ventileren door kieren of kieren afdichten.

Reports TNO-IMG research into ventilation of houses including the influence of cracks, open windows, weather conditions, occupants' behaviour, pollutants and guidelines. Lists conclusions such as an opened window renews the room air within half an hour. 40% of the occupants open windows for too long, 27%ventilate insufficiently, 25% of the dwellings are air tight, 75% leaky. Ventilation occurs partially through shafts (30%) and cracks (60%).Ventilation rates differ considerably between the rooms in a house.Ventilation ducts should have an exhaust function. Occupants should acquire some knowledge of ventilation, because it cannot be measured as temperature.