In tropical climates, how should building openings be arranged to maximize natural cross-ventilation given prevailing winds?

• A. Place openings on opposite façades to allow cross-ventilation.
• B. Align openings only on the windward side to direct breeze.
• C. Seal openings to minimize heat gain.
• D. Use interior ducts to move air.

Answer: (A)

Cross-ventilation relies on giving air a clear path through the space. When openings sit on opposite façades, wind-driven air can enter from one side and exit through the other, creating a continuous through-breeze that sweeps heat and humidity out of the building and cools the interior. This uses the pressure differences created by the prevailing winds to move air across the space.

If openings were only on the windward side, air would pressurize and rush in but have no convenient exit, leading to stagnation and less effective cooling. Sealing openings eliminates ventilation entirely, defeating the purpose. Relying on interior ducts to move air depends on mechanical systems rather than natural wind-driven flow, so it doesn’t achieve natural cross-ventilation.

So, placing openings on opposite sides best maximizes natural cross-ventilation in tropical climates with prevailing winds.