When I had only built homes in the north, exterior doors were not something that you really thought about other than whether they would swing to the right or the left. However they always swing to the interior of the home. This is called an “inswing” door.
However when I started to build in the Bahamas, I soon learned that the doors are all “outswing” doors and at first I thought it was just a custom. That was a wrong assumption as it has to do with hurricanes.
Outswing doors to a patio.
One of the features of an outswing door is that as water runs down the door on the exterior the threshold directs the water away . The second feature is that when the door is closed the bottom of the door is solid against the bottom threshold. Why is this important?
In a hurricane the pressure difference between the outside and the inside can be quite different and as a result the outside force actually tries to push the door to the interior. When this happens the door is literally pushing against the frame and the threshold because it is an outswing door. If you used an inswing door the force of the pressure would only be contained by the hinges and the lock and may end up giving way.
Here in the Bahamas there are many days when it is just so windy that leaving the house requires pushing the door open to the exterior (outswing) and holding on with 2 hands because of the pressure and wind and that’s not even a hurricane.
So if you’ve ever wondered why houses in the south have doors that swing out, you now know.