I have a ground floor brick apartment so I’m pretty well insulated from the summer heat for most of the day. If I can get the apartment cold enough at night by running fans (ventilation), I can often make it through the day without turning on the A/C.
That small room is the best case scenario because it has the box fan blowing in directly opposite the door which has a fan at it to pull the air out of that room.
The closest I get to the coldest night temperature is 4 degrees farenheit in that room. I’m guessing the walls are retaining some heat.
Is 4 degrees a respectable delta for $20 Lasko box fans or could I do better?
I’m cross ventilating as much as I can, but I have a weirdly shaped, weirdly windowed apartment and think I need about 3 more fans to circulate the air completely, but I don’t think I do better than what I have for that one room.


That’s the basic theory I’m going with. Imagine a Y. Each of the top ends are two rooms with one window each. They are connected via a hallway to my bedroom on the bottom, which has two window on the opposite side of the building. The wind has the slightest tendency to blow down that Y so I have the air move in that direction.
The only wrinkle is that even with two fans in that hallway to bring the air in, there’s still 3 temp difference between the top and the bottom, it gets to 1 if I flip one of those bottom fans to bring air in.
But I also have windows that open horizontally, so I have plenty of open air above the windows that I occupy with venetian blinds, so I could probably do a better job of sealing that up to improve flow and decrease backwash.
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Don’t forget to circulate the air within the rooms, not just move air through them. Even with airflow across the apartment, there’s often pockets of air that rarely get circulated. Also, things like furniture, closets, and stuff will hold heat and warmer air.
For me, often just a ceiling fan or a fan blowing vertically from the floor in larger rooms is enough to make a big difference.