I've been spending way more time than I had ever wanted looking for a ceiling fan for my living room which has a vaulted ceiling. I have a few basic requirements:
Decent quality, Includes remote control, No pull chain, No light. Not flush mount (does not work on slope ceilings). Large room (52" or larger blades).
My ceiling is 18.8 degrees slope and is 10 feet off the ground where the fan mounts. Due to the slope, the ceiling loses 10" of height over 26" (radius of 52" fan). So without a longer down-rod it would scrape the ceiling on the low side.
I couldn't find a single fan manufacturer spec that shows the minimum dimension of the the fan blade can safely be to the ceiling, so going with a couple inches clearance is good.
The MinkaAire New Era fan that met all the criteria is 10" from ceiling to blade. So with my slope ceiling drop I need a longer down-rod. But the fan cannot be lower than 7' off the floor for safety reasons and also it would look kinda stupid. The down-rod that is included is 6". They offer a 12" and 18" down-rod. Down-rods cannot be cut to length because they are threaded. The 12" down-rod will put the fan blades just over 8 feet off the ground and allow for about 6" of clearance off the ceiling at the low side. Hopefully that is enough.
Oh, and I did all this research without asking wife so if she doesn't like it I'm going to table-flip.
The only other options I found were a Hunter Fan Dempsey (not as attractive) and some no name fans (home decorators collection) at home depot.
Most fans seem to accommodate a 18-20 degree slope, but going steeper sometimes requires a steep slope adapter.
I did like the all stainless steel fans with metal blades but they all say blades must be 10' off the ground for safety reasons and the kinda makes sense.
Outdoor fans can be used indoors but the blades might be metal or plastic. I definitely did not want plastic blades.