Which statement about wind effects on buildings is true?

• A. The windward side experiences low pressure; the leeward side experiences high pressure.
• B. The leeward side experiences higher pressure than the windward side.
• C. The pressure differences are negligible in most buildings.
• D. The windward side experiences high pressure; the leeward side experiences low pressure.

Answer: (D)

When wind hits a building, it creates a high pressure on the windward surface where the air is pushed and slowed, while the flow around the sides and rear accelerates, producing lower static pressure on the leeward side. This pressure difference arises from stagnation of air at the windward face and flow separation and acceleration around the building, which pulls the pressure down on the leeward side. That contrast drives the wind loads and can influence doors, windows, and roof behavior, as well as moisture movement around the structure. So the windward side experiences high pressure and the leeward side experiences low pressure, making this the correct description. The other statements conflict with how air behaves around obstacles, and they don’t reflect the typical pressure patterns observed on buildings.