How to Vent a Bathroom With No Outside Access – 6 Best and Easiest Ways To Get It Done

Bathroom ventilation prevents mold growth, mildew, and lingering odors. However, venting a bathroom without outside access is easier said than done; HVAC systems cost consumers thousands of dollars to keep their homes comfortable throughout the year. Bathrooms are no exception, though ventilation in this room is often overlooked.  Mold, stale air, and foul odors can make people wonder how to vent a bathroom with no outside access.

Excellent bathroom ventilation can solve all these problems and more; it’s also something many homeowners can do without hiring a professional. Lighting can also be a key to making a comfortable stay inside. Regardless of the design or location of the bathroom, we’ll tell you the best ways to vent these areas when you don’t have outside access.

Proper bathroom ventilation isn’t just a matter of convenience; it’s also a legal requirement in most cities. Proper ventilation circulates air and controls moisture, which promotes mold and mildew growth, peels wall paint, delaminates cabinets, and rots framing. It also improves air quality and eliminates odors in the bathroom. A properly ventilated bathroom prevents excessive humidity, which can contribute to mold growth and spread throughout your home. Furthermore, prolonged exposure to high humidity can deteriorate drywall and discolor the paint.

Every building codes require tenants to install a bathroom fan without outside access. A vent fan will collect moisture-laden air and exhaust it outside the house. It will prevent mildew and mold growth. Some vent fans have lights illuminating the bathroom while reducing moisture levels.

Venting a bathroom is easier, but you can do it yourself or with professional assistance. Hiring a professional is best if you need to vent a toilet but don’t have outside access, but DIYers can do it just fine. Let’s look at how to vent a bathroom without external access, whether you add a ceiling vent or plug in a fan.

Is it Possible to Vent a Basement Bathroom on Your Own?

You can vent the basement bathroom on your own by installing a ceiling vent. If you vent your bathroom without professional assistance, you can spend up to a reasonable amount of money on parts and supplies. Both bathrooms should not share a vent, each requiring an exhaust fan.

A basement bathroom fan installation is a do-it-yourself project, whether a new wall bathroom exhaust fan or a ceiling bathroom exhaust fan is required.

Why Is Basement Bathroom Ventilation Necessary?

Bathroom activities such as bathing can add a significant amount of humidity to the air supply in your home. That airborne moisture can wreak havoc in your home if you don’t have enough basement bathroom ventilation. Not cleaning them will also promote the growth of mold and mildew, make the air feel sticky and warm, put undue strain on HVAC equipment, and increase energy consumption. These problems can be avoided by following these ventilation tips.

Unfortunately, many people are unaware that poor ventilation can harm your home and health. Many people believe that a basement bathroom vent fan’s primary function is to remove odors from a bathroom. But, the more important process is to exhaust warm, moist air, such as that produced by using a bathtub or shower. Warm, moist air promotes mold growth and damages bathroom fixtures and surfaces. If your bathroom lacks a fan and smells musty, you should install one—and check to ensure that serious mold growth hasn’t already begun.

Bathrooms without a bathroom vent fan are prone to excessive moisture buildup, which increases the risk of damaging bathroom walls, floors, ceilings, 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 levels in rooms can also deteriorate interior room materials like wallboard, paint, and trim, not to mention the entry door.

How Can Basement Bathroom Ventilation Be Improved?

Many homeowners overlook one of the most basic methods for improving bathroom ventilation: turning on the bathroom exhaust fan. We understand that many of you avoid using your exhaust fan because it is too noisy. While that noisy bathroom fan is annoying, ignoring bathroom ventilation is not a sufficient reason.

It’s far less expensive and risky to replace a bathroom fan with a quieter model than to subject your family to costly mold remediation. So, now that you know why you should start using your bathroom exhaust fan let’s talk about how you should use it to get the best ventilation.

Choose the Right Fan

If you’re starting from scratch and looking for a new fan, the first step is to measure your bathroom. A fan should provide eight full air exchanges per hour for optimal ventilation. Your fan’s cubic-foot-per-minute (CFM) capacity should be the same as the square footage of your bathroom. It means that if your bathroom is 60 square feet, you’ll need a fan with a capacity of 60 CFM.

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Once you’ve determined this, you can move on to choosing a model. You should be fine choosing one with all the bells and whistles you want as long as it has the proper CFM for your bathroom and works with your existing ventilation system.

Select the Best Location

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We understand your concern, and yes, there is a ‘best’ location for your bathroom fan. It should be near your bathtub or shower but not directly next to an air conditioning or heating vent. Also, remember that your bathroom exhaust fan should vent outside, not into your attic or another unfinished area of your home. The forced air can create air streams that interfere with the fan’s air intake.

Use it Regularly

A bathroom fan is useless if it is not used. Ideally, you should use your bathroom fan when you are creating humidity (while showering/bathing) and require additional circulation (ahem: toilet time). It’s also critical to leave the fan running for about 15 minutes after a shower or bath to remove moisture from the air completely.

Do you take a shower before work and can’t wait to turn it off? No worries. There are a few options on the market that have automatic timers and humidity sensors that turn on when humidity levels are too high.

Keep it Light

Even the best exhaust fans can’t compete with an open window. If you have the luxury of a bathroom window, open it! Another way to reduce moisture in your bathroom is to keep your shower door/curtain open after using it. It promotes evaporation and keeps water from accumulating in your shower.

Perform Regular Maintenance

While bathroom fans don’t require much upkeep, they’re also not a fix-it-and-forget-it fixture. To keep your fan running smoothly, clean it at least once every six months. Simply turn off the power to your bathroom, remove the cover, vacuum away the dust and cobwebs inside the fan (an upholstery brush works well for this), and reassemble it.

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Open that window, use the fan as needed, and clean up any puddles of water to keep the bathroom as dry as required when it comes to bathrooms. While a properly chosen and installed fan will reduce moisture and humidity in your bathroom, a little assistance never hurts. The breezier, the better.

How to Vent a Bathroom With No Outside Access – Detailed Insights

Step 1 – Choosing the Best Vent Fan

You must choose the best vent fan for your bathroom. Here are some of the considerations to make when choosing a vent fan.

Ratings for Vent Fan Size

The size of the bathroom should determine the size of your vent fan. The vent fan’s size is measured in cubic feet per minute (CFM). To determine the appropriate size vent fan for your bathroom, multiply the room’s square footage by 1.1. For example, if the toilet is 100 square feet, you must purchase a vent fan with a CFM rating of 1100 CFM.

Other factors to consider for large bathrooms include the presence of a bathtub, jetted tub, and shower inside the bathroom. To determine the proper vent fan size, add the CFM ratings of various fixtures in the bathroom. You must purchase a vent fan with a 100 CFM rating if you only have a basic shower and toilet. However, if you have a jetted tub, the vent fan should be 200 CFM.

Ratings for Vent Fan Sound

Vent fans have good ratings in sones as well. You should check the sound ratings to ensure the fan will not make too much noise inside the bathroom. Vent fans have sound ratings ranging from 0.5 to 6.0 sones. Purchase a vent fan with a good rating of one tone or less. The proper rating of the vent fan can be found on the packaging.

Vent Fan Type

You must purchase a ceiling or floor vent fan. A ceiling vent fan is preferred over a floor vent fan because it is easier to install. However, in some cases, such as if the bathroom is beneath a stairwell, you cannot vent through the roof. The ducts run between the floor and the exterior wall if you have a floor vent fan. Ask the contractor whether the fan can be installed on the ceiling or the floor.

Speed of Vent Fan

Variable-speed vent fans are available on the market. The vent speed can be adjusted using a remote or a button on the fan. Due to this, you will have more control over the humidity in the bathroom.

Step 2 – Installing the Vent Fan

The cost of installing a vent fan is determined by the location and type of fan established. You can do it yourself or hire a professional to install the bathroom vent fan. Installation of the fan and ductwork typically costs a reasonable amount of money. You will pay less if the ventilating duct and wires are already installed. You should budget accordingly if you intend to hire a professional to install ventilating ducts and fans. You can also do it yourself and install the vent fan.

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To install the fan, mark where the vent fan should go on the bathroom ceiling. Place the vent fan between the toilet and the shower to achieve the best result. Make different reference holes through the ceiling or floor with a 3/8-inch spade. Now, using the reference hole, determine the exact position of the fan. Place the vent between the joists, considering any obstructions such as pipes, wires, and insulation. Now, measure the fan dimensions and outline the intake port with a layout square.

Using a jigsaw, cut through the ceiling or floor. Make sure to wear safety equipment to avoid inhaling cement dust, which can be hazardous. After you’ve cut, you should put in the ducts. You will also need to connect the fan’s wiring to the outlet. If you are installing a floor vent fan, you may need to cut the tile and mark the location of the ducts. When installing the floor vent fan, you should also consider the location of the pipes. After installing the vent fan and all the wires, you should put it on the cover. Turn on the fan to ensure it is operational.

Step 3 – Reducing the Noise of the Vent Fan

Vent fans with a high CFM output are noisy. If the fan noise bothers you, you can install an inline fan. For best results, install the inline fan anywhere along the duct. You must ensure that the bathroom has adequate ventilation.

Step 4 – Allow the Fan to Run After A Shower/Bath

After you shower or bath, turn on the vent fan for at least 30 minutes. Turning off the fan immediately after leaving the battery will not result in proper ventilation. It is necessary to exhaust all of the steam in the bathroom completely. You can purchase an automatic humidity sensor, which will turn the fan on or off based on the humidity levels.

Step 5 – Cleanse the Ventilating Fan

Over time, the ventilation fan becomes filthy. A fan covered in dust or grime will not efficiently vent the air. To ensure proper ventilation, you must clean the fan every six months.

The following are the steps for cleaning the bathroom ventilating fan:

  • #1: Turn off the electrical power – Before cleaning the fan, turn off the bathroom’s electrical circuit.
  • #2: Take off the cover – The vent fan cover is held in place by wire pins. To remove the surface, you must squeeze the pins together.
  • #3: Remove the Fans – Use a vacuum cleaner to clean the fan. Attach a crevice tool or brush to the fan to remove any cobwebs, dust, or other grunge.
  • #4: Turn on the Power – After cleaning the fan, you should turn on the power.

Step 6 – Maintain a Dry Bathroom

Excess moisture should be avoided in the bathroom. Keeping the bathroom dry will eliminate running the fan for extended periods. As a result, the bathroom vent fan’s lifespan will be extended. To keep the floor dry, consider using an absorbent mat. Drips and puddles in the bathroom should also be cleaned.

Taking a cooler and shorter bath can also help to reduce moisture buildup. It will dehumidify the bathroom and help to reduce condensation. Keeping the bathroom dry will reduce the time you need to run the fan. It will also reduce the possibility of a slip and fall accident.

Final Takeaway

A poorly ventilated bathroom will make everyone in the room feel uneasy. It is something you can solve by installing a vent fan. Installing a vent fan will eliminate odors, moisture, and mold growth. The cost of installing a ventilating fan is one of the reasons most people do not do so.

However, installing the vent fan will be worth the cost. It will result in a cleaner and less odorous bathroom. You’ll be glad you installed the ventilation fan because it will create a more pleasant bathroom environment.


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