Comments by "Scott Franco" (@scottfranco1962) on "Portable Air Conditioners - Why you shouldn't like them" video.

As another video went into, the air does not just come through the walls. Most or all homes are built with an expansion gap between the sheet rock on the walls and the framing/joists. It is there to prevent the sheetrock from cracking due to expansion. Those gaps add up - you probably have more than a square foot of total space that comes from the outside. But outside.... where? exactly? There is the rub. Most commonly the outside is the attic, and the pathway into the house is through the walls and into the rooms via the various electrical and other outlets. In fact on some houses you can even see a trail of dirt next to an outlet from years of such "negative pressure" ventilation. You are drawing air that is dirty and dust filled from your attic into the house.
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