A herniated disk, sometimes (incorrectly) called a slipped disk, is a common cause of severe back pain and sciatica. A disk in the lumbar area becomes herniated when it ruptures or thins out, and degenerates to the point that the gel within the disk (the nucleus pulposus) pushes outward.
The ceiling fan's downrod must be long enough for the fan's blades to clear the ceiling. A fan with a 12-inch downrod works for a vaulted ceiling with a one-quarter-to one-third-inch pitch. An 18-inch downrod is sufficient for a pitch that is five-twelfths to one-half inch.
Blog. The quick answer: install your fan so that the blades are at least 7 feet from the floor. If possible, install the fan so that the blades are 8â² â 9â² above the floor. Long answer: Most ceiling fans come with a short downrod (about 3-4 inches in length). Most ceilings are 8 feet high.