"Anthony Matonak" wrote in message

I wouldn't even know how to go about measuring how much air a
box fan moves when mounted in a window. When I tried it, it
seemed that covering all but the area of the fan blades seemed
to work better.

Anthony

Years ago, window fan were made like that. Them mounted in the window and
had baffles on either side so it sucked air through the house. To make them
cheaper and more portable, the box fan was invented. Often, they suck air
in from the window and blow it right back out and not from through the
house. The cfm is an important measure, but lower cfm drawing across the
room is better than higher cfm just sucking in air and blowing it right back
out.