Passive Ventilation
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.
Prevailing Wind
Check wind speed and direction during the hottest season and design to capture prevailing winds.
Openings
Ventilation openings can be created using hit and miss bricks, metal, timber or concrete screens or louvres.
Cross Ventilation
Windows and vents on opposing sides of a building benefit from wind driven cross ventilation, particularly if they face the prevailing wind direction.
Stack Ventilation
Buoyancy-driven stack ventilation uses temperature differences to move air. This can be enhanced by solar chimneys driving faster ventilation.
Night Cooling
Permanent ventilation openings allow cool night air to circulate the building, reducing heat build-up gathered by the structure during the day.