At home, my treadle is along a wall. I have enough space for a floor lamp and a sewing basket. Hook in the ceiling, have my gravity feed water bottle hanging up, a shelf for the iron, board in the wall. I hang up what I am working on. So, technically 4'x3' at most, and only when my chair is out. Takes no more space then a desk.
My work room is 35'x22', where my mirror and fitting room/office is 8'x20' 2800 square feet.
Thing is, you work in whatever area you have, honestly.