I worked 3 1/2 years in the largest home warehouse in the light and fan dept. There is as far as I know a specified distance from ceiling. I can tell you for sure that Flush mounted and/or so called Hugger fans are not as effective as those on down rod. I believe from 2 to 5 feet seems best. The suggested hieght from floor to bottom of fan(or light kit) should not be less than 7 feet and more if a tall person in family.