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As a young man I worked for my Dad hanging ceiling fans on displays in showrooms all over the Southwest. Every year the new styles would come out and I would have to take down the old and put up the new. Through the years I learned many useful and interesting tips and tricks about ceiling fans. In this article I will tell you how to size a fan for proper air flow in a room. Don’t let this intimidate you, it is easy and straightforward.
Buying a ceiling fan that is not the right size for the room you install it in will cause a great deal of dissatisfaction and disappointment in the long run. When you are taking on a home improvement project I know how enticing it is to just get the job done. You have so many things to do you want to finish the job and move on. Installing a new ceiling fan in your home is a great project to take on, you just want to make sure you do it right the first time so you can enjoy the breeze for years to come.
Ceiling fans are all about moving air in a room to maximize comfort. If your fan is either too big or too small for the room it is in, the airflow will be wrong and you won’t get the comfort benefits of the fan. In fact, if the ceiling fan size is wrong, you’ll probably be frustrated by it all the time. If a fan is too big for the room it can create an unmanageable vortex of wind blowing papers and things all over the place. It might also create too much noise and be a general distraction. If the fan is too small the room won’t get much airflow and you might not even notice it is there.
If your fan is either too big or too small for the room it is in, the airflow will be wrong and you won’t get the comfort benefits of the fan.
If you are going to take on any project, make sure you do it right. It is essential that you choose a ceiling fan that is the correct size for the room it is in.
Here’s how to determine the proper ceiling fan size you need for a given room.
Step One
Measure the size of the room you wish to install or replace a ceiling fan. Take the length of the room x the width of the room, this gives you the square footage of the room.
For example: a 10×12 room is 120 sq. ft.
Step Two
Determine the height of your ceiling. Standard ceiling heights have changed over the years, older homes usually have eight foot ceilings, where newer homes can have ten or twelve foot ceilings. You can buy a laser room measurer online or at your local hardware store for very accurate measurements. Or have someone hold a 25ft tape measure against the floor, while you go up the ladder to determine your ceiling height.
Step Three
Now you know the height and square footage of the room, it is time to choose which size of fan will be best. Below is a list of suggested blade lengths for fans to fit different sized rooms:
50 sq. ft. or less: 29”-36” diameter of fan
50 sq. ft. to 120 sq. ft.: 42”-48” diameter of fan
120 sq. ft. to 250 sq. ft.: 52”-54” diameter of fan
250 sq. ft. or larger: 60”-62” diameter of fan
There are much bigger fans out there for really large scale rooms, if that is the effect you are going for.
If you have a room larger than this you will likely need to install two fans equal distance from one another.
Step Four
Next is downrod length:
8’ ceiling: Use included downrod (normally 3”) Placing the bottom of the fan 7’ above the ground.
10’ ceiling: 12” downrod Placing the bottom of the fan 8’ above the ground.
12’ ceiling: 24” downrod Placing the bottom of the fan 9’ above the ground.
Note: If your fan has a light kit, reduce the length of the downrod by 12” as the height of a light kit is usually 12”. This will give you the right height, either from the floor or on a ladder, to be able to replace the light bulbs.
Most ceiling fans only come with a very short downrod. You’ll most likely need to purchase a longer downrod if you have higher ceilings than the standard 8 feet. Downrods come in different installation styles, lengths, and finishes. If you buy a Casablanca fan, for example, be sure you buy a Casablanca brand downrod. Not just any downrod will fit the brand of fan you buy. Make sure you get one that matches your fan and the height you need.
It is tempting to just use the little downrod the fan comes with so you can get the job done, but if you have higher ceilings you really want to get a downrod with a proper length for the room. Doing so will make the fan so much more effective and enjoyable. Also, if you decide to install the fan with a shorter downrod than is recommended, you may not be able to fix it in the future if you cut the wires too short. Once those wires are cut you are stuck with that downrod length. If you think you may want to bring the fan down lower, in the future, leave at least an extra 12-18 inches of wire inside the canopy. I use a twist tie to keep it tight and out of the way when hanging the fan. Also remember that room pitch may come into play and on a slanted ceiling you may need a longer down rod in order for the fan to work at all. If the blades are hitting the slanted ceiling, you’ve just created more problems for yourself. Do yourself a favor and make the necessary measurements described above before you go buy that beautiful new ceiling fan.
Adding a ceiling fan brings beauty, versatility, and new life to a room. And that is it! Now you know what you are looking for when you go shopping for your new fan.