Down rods might be a bit confusing for many people. The first question is likely which length you need and how a down rod helps a ceiling fan. Here’s what you want to know.
Ceiling fan down rods are used to get the blade assembly mounted at the correct height. The correct length rod makes the ceiling fan more efficient, safer and allows height adjustments for other reasons. Low profile fans without down rod tend to be less efficient but are sometimes the only option.
Down rods have a few different purposes which you can find below as well some advice on if you should change the length rod on your fan.
How a Down Rod Helps a Ceiling Fan
So what’s the deal with these down rods? Do you even need one and what do they do?
First I should mention that not all fans have a down rod. So called ‘low profile’ or ‘hugger’ fans don’t come with one since their goal is to stay as close as possible to the ceiling and don’t come down too much. The whole point of a down rod is to bring the blades of the fan down lower. Low profile fans have their place if you have low ceilings but otherwise one with a down rod is advisable since you have more control.
There are a few things that are impacted by down rod length;
The most important role of down rod length is safety. A ceiling fan has relatively sharp blades spinning quickly above your head. Or what should be above your head. You really don’t want there to be a chance that you could get your head, body parts or other things caught in the spinning blades. This can do quite a bit of damage. And even if you think you’ll be careful, people forget things and guests might not be aware of the danger at all.
That’s why in building codes around the US, you can find that the bottom of the ceiling fan blades should be at a minimum of 7’ (213.4 cm) above the floor. This is the minimum height. 8’-9’ is a much better height. 7’ is still easily reachable if you lift up your hands for most people. Do you stretch when getting out of bed or when getting off the sofa? In that case there is still a good chance 7’ is too low.
At 9’ there is little chance you’ll get anything caught in the spinning blades so you don’t have to worry about it. Of course you’ll still have to be a little mindful with brooms, mop handles and other long things.
Who’s going to check this if you mount the ceiling fan yourself? Probably nobody (unless you’re selling the place) but you still don’t want the chance of potential bodily or material harm done by a ceiling fan so it would be wise to follow the recommended heights.
So why not put the blades as close as possible to the ceiling? Wouldn’t that be the safest? Yes it would but now you start losing efficiency.
A spinning fan moves air from above the blades and pushes it down. This creates a low pressure area above the blades. This has to be replenished from the sides. The closer the blades are to the ceiling, the smaller the gap and the harder it becomes to refill the low pressure area. This means the fan has less air to ‘grab’ and push down. To move the same amount of air (as with a lower mounted fan), you’ll have to turn up the speed which means more power and a decrease in efficiency.
Eight inches is the minimum amount of clearance between the ceiling and top of the blades while more than 12” doesn’t have a major effect for average sized fans. That’s why you see 8”-12” down rod recommendations, even on a lower ceiling. Very large fans (72”+) can sometimes benefit from a little more clearance.
The airflow will feel a bit different depending on the height you mount the fan. The closer the fan is to you, the more direct airflow you’ll feel. The further away it is the calmer/slower it will feel but spread out over a larger area. Again, the 8’-9’ height is a good compromise for most people. But if you don’t need much direct cooling but like more air circulation, you could go a bit higher.
However, if that comes at the expense of the 12” clearance between the blades and the ceiling, you’ll be hurting circulation so you’re better off with the normal mounting height.
The down rod is also a tool to make sure the fan clears everything in the room. If you’ve got a vaulted roof, a long down rod is necessary to make sure the fan actually fits. However, it can also be used to let a fan clear a large wardrobe or other furniture.
If you have to sacrifice either clearance from the floor or from the ceiling to get the correct clearance, sacrifice the clearance from blades to ceiling. Safety should be the first concern. A trip to the hospital would cost way more than the bit of electricity from lost efficiency anyways.
Should You Change Your Down Rod?
Now you’ve discovered that the down rod on your fan is not quite the right length. Maybe it’s too close to the ceiling or too close to the floor. Should you change it?
In my opinion, if there is a safety concern, the down rod should be changed. Safety should be first on your mind and you really don’t want to take any risks with quickly spinning blades.
If the blades are too close to the ceiling, it’s an efficiency question. If you’re not happy with the performance of your fan and have the ceiling height for a longer down rod, you can try a longer one. For most fans 12” from the ceiling is perfectly adequate. For very large diameter fans 18” could provide an improvement. You probably won’t really notice a difference in your electric bill unless you use very little electricity otherwise. While down rods are not expensive, you probably won’t be able to make that amount of money back in a lower electric bill quickly. Over a couple of years you might though.
The big benefit of improving efficiency is that you might be able to make your current ceiling fan better to the point where you don’t have to buy a new one. Now that is a pretty good saving right there. Down rods are a whole lot cheaper than a whole new fan.