Feasibility of controlled hybrid ventilation in mid rise apartments in the USA

Natural ventilation is generally accepted as the preferred ventilation option as it is a healthy and energy-efficient means of supplying fresh air to a building. In the USA it is seldom being applied as most climate zones are considered unsuited to apply natural ventilation, mostly due to perceived uncontrollability and very humid and hot or very cold seasons. For mid and high rise apartment buildings the option of natural ventilation is virtually disregarded because the tradition of full air conditioning is so well established. This paper challenges this disregard and hypothesizes that controllable ventilation openings are a realistic option for apartment buildings in some climate zones. As envelopes without operable openings pose fewer security and facility management concerns, a convincing case has to be made before people are willing to experiment with non fully air conditioned solutions.