Are there any STATISTICS as to why a hip-roof is better at withstanding wind with comparison to gable roofs?
Answers:
If the wind is blowing directly at the end of the gable, there is more surface area at right angles exposed to the wind. A hip roof will be slanted and this tends to make the wind flow over the roof surface.
If the wind is blowing across the roof, then a hip roof has less projected area exposed to the wind and therefore there is less force applied to the roof.
Think about it this way. You have a sheet of plywood laying flat on the ground. Now begin to lift one end up into the wind. The more you lift the end of the sheet the more force you will feel applied to the sheet of plywood.
I realize there is no math in this answer but I think this is a simpler way to understand what is happening.
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