Why You Need a Bathroom Vent Fan

Remove Moisture From Your Bathroom With a Vent Fan

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A bathroom vent fan is a mechanical ventilation device that utilizes ducting the inside air outside via a flexible hose, drawing out moisture, odor, and fumes from within the bathroom outdoors, improving the air quality within the bathroom.

Purposes of a Bathroom Vent Fan

A bathroom vent fan is an important part of every bathroom in the house. You may think that its only purpose is to exhaust smelly air from the room, but in fact, its more effect use is to remove warm, moist air from the interior of the bathroom to the outdoors. Warm, moist air not only encourages mold growth but also can cause damage to a bathroom. If yours doesn’t have a bath fan and it smells musty, it’s likely you need to install a bath fan. In fact, local building codes sometimes require that you install a bath fan that is sized to the specific area of your bathroom, but not always, so check with your local code enforcement officer for your specific area's regulations.

Potential Problems Without Bathroom Vent Fans

Without a bathroom vent fan, bathrooms are susceptible to excessive moisture buildup that increases the chances for damaging bathrooms and bathroom fixtures. Warm, humid air, caused by running hot water for baths and showers, is a perfect environment for mold, mildew and microorganism growth. High moisture in rooms can also breakdown interior room materials like wallboard, wall paint, and trim, not to mention the entrance door. For a safe, healthy bathroom, ventilate.

Bathroom Vent Fan Choices

Bathroom vent fans vary in styles and colors. They sometimes come complete with a light and sometimes even a heater option. They are usually controlled by either a single-pole switch or a wall-mounted timer. Placement of your bathroom vent fan varies on your preferred position. You may want the fan either over the toilet or possibly in the center of the room.

Bathroom Vent Fan Tips

Be sure that the vent flapper is installed properly to close when the fan is not in use. This keeps the cold air from the outside from filtering back into the bathroom. In fact, the flexible hose should be insulated with insulation to keep condensation from building up from the difference of temperature between the inside and outside air temperatures.

How a Bathroom Vent Fan Extracts Air

The air is drawn out of the bathroom from the fan enclosure and extracted via a fan. The fan pushes air out through a plastic flexible hose that is attached to the fan enclosure and the louvered cover plate vent. This vent is cut into the wall or roof and attaches to the outside with four screws and some silicone caulk or covered by a roof boot. The flexible hose is connected to the aluminum piping attached to the plastic vent housing that exhausts the air outside safely.

  • Bathroom Size / Minimum Ventilation Required (CFM)
  • Less than 50 Sq. Ft. / 50 CFm
  • 50-100 Sq. Ft. / 1 CFM per Sq. Ft.

Special Circumstances for Bathroom Ventilation

  • Install a bathroom vent fan in an enclosed toilet room.
  • Allow a 3/4" air gap below the entrance door for required makeup air.
  • Install wet location approved bathroom vent fans over the shower or tub when possible.
  • Rooms with ceiling heights over 8' may require additional venting.
  • Choose quality bathroom vent fans based on CFM's and noise level ratings for each.

Suggested bathroom vent fan ratings of 1.0 or less are the best choice.

Choose an HVI-Certified Bathroom Vent Fan

  • Products are independently tested and certified to meet specific industry standards.
  • Properly sized and installed products will produce proper ventilation for air quality.
  • Products guaranteed to perform as promised.

In order to choose, size, install and wire the perfect bathroom vent fan for your home, we suggest reading the following topics: 

Bathroom Electrical Codes

What does the NEC require in different parts of the home? This section will deal with bathrooms and its safety.

The National Electrical Code (NEC) was written to provide a set of rules and regulations to keep the use of electricity in your home safe. Here are the top bathrooms codes you need to live by to remain safe and keep your electrical devices working properly.

Each bathroom should have a circuit for lighting and an exhaust fan. This may include a blower-heater-light combination.

Choosing Bathroom Fan Locations

Installing a bathroom fan seems easy, but there is much more to installing it in the ceiling then you may think. Simply getting a saw out and cutting a hole may lead to ceiling damage and a lot of drywall patching in the end if you aren't careful.

We should first consider three things before we break out the power tools to cut the hole the fan will eventually fit in. First, the fan should be located in the area of the bathroom that is exposed to the largest amount of moisture.

How to Size a Bathroom Exhaust Fan

In order to keep bathrooms free from mold and mildew, bathroom exhaust fans remove moisture and odor quickly and easily. The real secret is getting the right sized exhaust fan for the proper room size.

Know What Is Required Electrically In A Bathroom

Bathrooms are damp and have special needs when wiring them. This article will help you install appropriate electrical wiring to cover lighting, air flow, and safety devices in your bathroom. Everything from watertight lighting fixtures in bathing areas to effective ventilation to GFCI outlets for safety should be observed.