In a previous apartment I had Jerry-rigged a whole-house/attic fan by putting a box fan in the space where the hatch to the attic was. I used triple-wall cardbo

In a previous apartment I had Jerry-rigged a whole-house/attic fan by putting a box fan in the space where the hatch to the attic was. I used triple-wall cardboard and duct tape to make it the right size. It really helped pull air in from every open window, and because it was at the top of the steps it helped exhaust the hottest air in the house. Box fans are not made for that type of application, but it worked. If I had to build my own again I would use a better fan, and use a smart home device to turn it on and off.