When we added on my sewing room, I thought that 18 x 18 was a large enough space. By the time I got my 10' frame, table for cutting, large ironing board, and had collected all my sewing stuff that had been stored all over the house, I had run out of room. Partly from some poor planning on my part as to what I wanted
and not wanting to give up some other stuff. As they say, hindsight is usually better than foresight.