Ventilation is needed in all buildings to remove odour and provide us with oxygen. In hot climates, like East Africa, adequate ventilation is essential to provide cooling. ‘Passive’ ventilation through windows and opening vents is the cheapest and simplest form of providing fresh air.
Where there are problems with ambient noise or pollution, often in more urban locations, mechanical ventilation can be necessary, but passive ventilation should always be the default solution. Openings should be carefully designed to improve thermal comfort.