With Bernoulli’s principle in mind (I think that’s the right one), is it more efficient to vent a room by putting a fan back from a window a bit, or right up next to it, and if so, is there a general sweet-spot as to how far back it should be?

Question

For context, this would be to vent a basement bathroom with a a window in an old house, and I can’t install a bathroom vent.

In: 857

Answer 1

>is it more efficient to vent a room by putting a fan back from a window a bit

Yes

>is there a general sweet-spot

The fast moving jet of air will expand into a cone, picking up more air and slowing down. The sweetspot is where that cone roughly fits the size of the window, but the actual distance depends on size of the fan, speed of the fan, window size, and window shape.