It is always good to let steam off, or the consequences can get messy. We?re talking about vent fans in the bathroom, of course.
If you don?t have a bathroom vent fan yet, a bathroom redo is the perfect time to set this to rights. A lot goes on in a bathroom remodel, so you might overlook this, but you really should not. A vent fan is a simple device. And all it really does is suck out the wet air out of your bathroom. Without it, though, you could be looking at another major redo much sooner than you should.


bathroom mold

Most people think vent fans are just to keep the bathroom smelling fresh, and while that is their clearest use, it is not the key reason to have them there. The most important function of vent fans is to suck out the moisture out of the bathroom, along with the bad smells, of course.

Anyone that has ever used a bathroom would know that it is almost always humid, even if the bathroom walls and floors are dry. This is because most bathrooms are closed, confined spaces with just a small window (if any) to provide some type of outlet for warm, wet air.
Bathrooms tend to be moist in most cases, especially the ones people use regularly. As most people prefer to keep bathrooms out of sight, the closed door makes this worse.

High levels of humidity tends to encourage mold and mildew over time. So the best way to prevent that is to keep humidity levels low. A vent air can keep humidity as low as possible because it forcibly ejects warm, wet air out of the room. Mold and mildew can lead to a nasty smell in your bathroom, and might even cause damage to some structures, making a major bathroom remodel necessary.

Molds and mildew are not the only things about which you have to worry. Wood and wallpaper does not react well in the presence of moisture. If you have anything like that in your bathroom, they are bound to start showing some type of damage over time. Moisture can also rust or corrode some types of bathroom fixtures, so there?s that.

You might also want to check out the building code in your area. Some do require vent fans in bathrooms for safety and health reasons. If that is true of your area, not having one can get you into trouble. Find out more about these building codes with your remodeling contractor.

Fan facts

diagram of vent fan
A vent fan is not a complicated piece of machinery. It works along the same principles as any type of fan, which draws in air when the blades rotate. In most cases, this requires the blades to be at an angle between 12 and 15 degrees to create a sort of air current. A vent fan typically works in conjunction with a duct to lead the air out if there is no direct access to the outside. You need to keep it running in order to draw in air and push it out of the bathroom.

The ability of the fan to draw in or put out air depends on the number of the blades, the angle, and the speed at which it rotates. As a rule of thumb, more blades, a steeper angle, and higher speeds mean a stronger draft.

Tech specs

person installing a vent fan

Choosing the right vent fan for your bathroom usually depends on the size of the bathroom, and the position of the fan. The code requirements may specify this. But there is no such thing in your area, here are some things you should know.


You may notice that all fans come with a CFM or cu ft./min rating, which is ?cubic feet per minute.? This is the airflow speed of that particular unit, which when it comes to vent fans refers to the speed at which the fan can remove the air from a room.

The CFM you need will depend on the room size. If your bathroom has a standard 8-foot ceiling and has an area of 49 square feet or less, you can typically make do with a 50 CFM fan. For bathrooms between 50 and 100 square feet, your vent fan should be equivalent CFM. For instance, if you have an 80 square foot bathroom, you need an 80 CFM vent fan.

Another factor you need to consider is the height of your ceiling. If it is more than 8 feet high, you need a vent fan with higher CFM than usual, or you can put in two or more fans.


Most people put vent fans nearest the doorway overhead to act sort of like an air curtain, keeping the bad smells from escaping. That is not always the best place for keeping your bathroom moisture free, however.
If you have a shower stall or bathtub that creates some steam, it makes more sense to put it over that. You just need to make sure it is not so near that it is within arm?s reach while a person is standing on water. If that is unavoidable, choose a vent fan rated for ?wet? use.

Code requirements

Not all areas have a local building code for vent fans. But you still have the National Electrical Code you need to follow for bathrooms. One of the things this code specifies is that you need a dedicated circuit for vent fans. It should also need grounding to prevent electrical shock.


You need a vent fan in your bathroom for so many reasons. The best time to put them in is during a bathroom redo. Make sure you include them in your plans from the beginning, and make sure your contractor is reliable about putting them in. Mimosa Kitchen and Bath knows all about bathroom remodeling, including lighting design, product, and installation. We are the best choice for you if you are in the DC metro area, Columbia, Rockville, Bethesda, Jessup, Chevy Chase and surrounding areas.

Aside from expert wiring and remodeling services, we sell high-quality products, including vent fans, manufactured by leading brands in the industry. When you purchase your products from us, you are guaranteed a speedy delivery compared to ordering from big box stores. Our contractors will fabricate the product and install it into your bathroom quickly and with excellent artisanship.

We sell a host of products, from bathroom and kitchen cabinets, flooring, faucets and sinks, to vanities. Some of the brands we carry include Zodiaq, Fabuwood, Forevermark Cabinetry, Caesarstone, MSI, Kitchenmaid, Wolf Cabinets, Cambria and Hardware Resources.
You can visit our showroom in Ellicott City, Maryland to see the many products and stone slabs we have available. This includes marble, granite and engineered quartz for your vanity tops.

All of our products come backed with brand warranties.
Contact us today to get a free quote and design consultation for your bathroom remodeling project!