Whole House Humidifier Pros and Cons: Everything You Need to Know

whole house humidifier pros and cons

In the quest for a comfortable and healthy home environment, many homeowners are turning to whole house steam humidifiers. These devices work with your home’s furnace and can significantly improve indoor air quality by maintaining optimal humidity levels.

But like any home improvement investment, weighing the pros and cons before deciding is key. Let’s look at the whole house steam humidifier pros and cons:

Pros of Whole House Humidifiers

  • Automatic Humidity Control: Whole house humidifiers are equipped with humidistats, allowing for the automatic regulation of indoor humidity to maintain comfortable levels.
  • Improved Air Quality: By maintaining optimal humidity levels, these systems can reduce the presence of airborne viruses, bacteria, and mold, potentially improving respiratory health and alleviating dry skin conditions.
  • Comfort: Properly humidified air can minimize issues like dry skin, itchy eyes, and chapped lips and can make the air feel warmer, possibly allowing for lower thermostat settings and energy savings.
  • Preservation of Home and Furnishings: Balanced humidity can help preserve wood floors, furniture, and musical instruments by preventing them from drying out and cracking.
  • Low Maintenance: Once installed, whole house humidifiers generally require less maintenance than portable units, needing only periodic changes of the evaporator panel or similar components.
  • Energy Efficiency: By making the air feel warmer, these systems can reduce heating costs as you may be able to keep your thermostat at a lower setting.

Cons of Whole House Humidifiers

  • Expense: The cost of purchasing and installing a whole house humidifier can range from $400 to $1,200, which may be prohibitive for some homeowners.
  • Professional Installation: These systems typically require professional installation, which adds to the initial cost and must be done correctly to avoid issues like mold growth.
  • Risk of Mold and Mildew: If not maintained properly or if the humidity levels are set too high, there is a risk of promoting mold and mildew growth within the home.
  • Potential for Over-Humidification: Without proper regulation, whole house humidifiers can create excessive humidity, leading to condensation on windows and other surfaces.

What is a Whole House Humidifier?

Unlike whole house dehumidifiers that remove moisture, a whole house humidifier adds moisture back into the air with low humidity.

Whole home humidifiers also differ from room humidifiers in that they moisten the air for your entire house. There are two main types of whole home humidifiers:

Portable Whole Home Humidifier

These free-standing humidifiers will evenly distribute controlled humidity throughout your home without being connected to any ductwork. They are also pedestal-style or console-style humidifiers and can accommodate up to 2500 square feet. They are generally loud and have limitations to their effectiveness.

HVAC Central Whole House Humidifiers

Whole house humidifiers attach to your ductwork near your furnace or indoor air handler. The specific installation location depends on the humidifier model, but they are usually installed before or after the furnace filter. Newer humidifiers have a powered fan that evenly spreads humidity throughout the duct system.

Many humidifiers will activate after the heating system is turned on. They’re usually automatically managed by a humidistat, which functions similarly to a thermostat but monitors humidity instead of temperature.

whole house steam humidifier

Whole House Humidifier Pros and Cons Explained

There are several pros and cons to furnace humidifiers. Here are some of the top advantages of having a whole-house humidifier:

1. Automatic Humidity Control Throughout Your House

One of the best things about portable and HVAC whole-house humidifiers is that they keep indoor humidity comfortable. When cold outside and the heat is on, dry air can worsen allergies, cause dry skin, make floors creak, and be uncomfortable. Humidifiers help counteract all of that by adding moisture to the air.

A whole-home humidifier has a humidistat, allowing you to set it to the desired humidity level in your home. This is ideally 40% to 45%. The central humidifier will then release moisture until the relative humidity in your home reaches the desired humidity level.

Humidistats are important because if indoor humidity exceeds 50%, mold and bacteria are more likely to grow. The humidistat will automatically regulate and maintain moisture levels.

2. Consistent Humidity Levels Prevent Damage

If you have a portable humidifier, you must be careful about how much moisture it puts out. If it is too much, it can damage your walls and furniture. There is also a risk of mold growth.

With whole house humidifiers, this is not a concern. The unit will cycle intermittently to regulate and maintain a constant humidity level in your home.

3. Central Installed Humidifiers are Low Maintenance

HVAC whole-house humidifiers need little maintenance compared to portable models. The evaporator panel filter should be changed once a year with ducted humidifiers, and at that time, it should also be cleaned to remove any mineral scale debris. The upkeep is almost non-existent other than the yearly evaporator panel change.

You must regularly clean your portable humidifier to prevent mold or other buildups. Try cleaning it every two weeks and adding an anti-microbial agent to the basin. How often you fill the reservoir with water depends on the unit size and how much you use it.

4. HVAC Central Humidifiers Have No Tank to Refill

An HVAC central humidifier connects to your plumbing to add moisture to your air without needing to refill a tank every few days. The humidity levels in your home are automatically managed for you.

5. HVAC Central Humidifiers are Quiet and Out of Sight

While a portable humidifier might be a visible eye-sore and make noise, a whole-house central humidifier system is hidden and very quiet. It’s installed next to the furnace or air handler, usually inside a basement or attic and out of sight from family and guests.

Because they are hidden, the noise output is not heard other than what you usually hear from the furnace or air handler operation.

6. Improved Indoor Air Quality

The Mayo Clinic cites several health benefits of a properly humidified indoor air environment. The relative humidity should be 30% to 50% for the best results. 1

Moisture reduces allergies and other respiratory conditions. People also have fewer issues with chapped lips, sore throats, dry skin, and sinus irritations when the relative humidity is within the ideal range of 30% to 50%.

Low humidity levels can cause health problems and make life uncomfortable. It can also be bad for your floors and furniture. There is now additional research that shows that low humidity levels increase the incidence of the flu virus.

When mice were exposed to a restricted humidity environment at Yale University, they discovered that the Influenza A virus caused their immune system responses to be hampered. 2

7. Health Benefits

According to the Mayo Clinic, having a properly humidified indoor air environment with the ideal indoor humidity ranging from 30 percent to 50 percent has several verified health advantages.

The following are some of the health advantages, including:

  • improved skin conditions, such as dry skin, itchy skin, and chapped lips
  • reduced allergy symptoms
  • fewer asthma attacks
  • sinus infections become less frequent
  • reduction of mold and bacteria, which is linked to bronchitis and other respiratory problems
  • cold and flu symptoms, like coughing, mucus congestion, and sore throat, become reduced in frequency

If you live in an area with large temperature changes between seasons, it’s vital to maintain the suggested humidity levels. A whole home humidification system will aid in protecting your health from humidity-related issues while increasing your comfort.

Not only does it improve your health issues, but good indoor air also makes your living environment much more comfortable. Furthermore, it helps preserve your home’s wood floors, furniture, and other valuables.

8. Added Value

Adding a whole-house humidifier makes your home more valuable and easier to sell, particularly to buyers who are hyper-sensitive to allergies or asthma. It’s an improvement that makes it more attractive to buyers.

whole house portable humidifier

Whole House Humidifier Cons to Consider

As with any home product, homeowners always have a few downsides to consider when buying or using a whole-house humidifier.

1. They Have a Higher Upfront Cost Compared to Portable Humidifiers

A whole house central humidifier with professional installation will cost $600 to $2500, depending on the humidifier type and coverage.

You can buy a whole house humidifier online for around $150 to $600. If you want to install a high-quality steam humidifier, it will cost you an additional $250 to $500.

Make sure you hire a qualified HVAC technician to do the job for you. If you have DIY abilities, install a whole-house humidifier in 2 to 3 hours. 

You should know that if you have multiple HVAC systems, you’ll need to install an appropriately sized whole-house humidifier for each HVAC system to achieve even whole-house coverage.

A portable whole-home humidifier is less expensive than an HVAC central model. You don’t have to pay for installation because it isn’t connected to the furnace. All you need to do is assemble it, fill the basin with water, and turn it on.

2. You Have to Clean Your Humidifier to Avoid Mold and Mildew

The disadvantage of whole-house humidifiers is that if you don’t maintain them, mold and mildew can grow in your HVAC system or within the portable humidifier. This is frequently caused by failing to clean the filter on your heating unit regularly and not cleaning a portable unit every two weeks.

Though inline whole home humidifiers need less maintenance, their portable counterparts need more cleaning and water changes. If you do not adequately maintain either type of humidifier, mold, and mildew can grow in your HVAC ductwork or inside the portable unit.

I’ve found mold inside furnaces a lot in the Southeastern United States. This is often because whole-home humidifiers add a lot of moisture to the air. When this happens, the furnace air filter doesn’t change often, so excess moisture accumulates over time.

Dust is a mold food source, so mold can grow when you mix uncontrolled dampness with dust. You will still want to clean the equipment every two weeks and, if possible, use a fungicide in the basin.

3. Hiding HVAC Air Leaks

If your home was built using older building codes, a central furnace humidifier could be hiding a bigger problem with air leaks in your home. More often than not, when we inspect houses, we find disconnected or unsealed air ducts with large holes or missing tape. These issues usually result in low humidity levels.

When installing a whole house central humidifier, ask your HVAC technician to inspect and repair air leaks in your ductwork.

A poorly insulated attic might be another source of moisture. A competent HVAC contractor can check for air leaks on your property. We have documented the benefits and drawbacks of whole-home humidifiers. Now is the time to consider installing a whole home humidifier to maximize comfort and health in your house.

whole house humidifier

Whole House Humidifiers vs Room Humidifiers

Whole home humidifiers and room humidifiers come in different sizes. Room humidifiers are much smaller and hold less than one gallon of water. Pedestal whole-house humidifiers can work for homes up to 2500 square feet.

Whole house central models work best for 5000 square feet or fewer homes. Larger homes with multiple HVAC systems will need a humidifier per HVAC system, which can significantly increase installation costs.

Are Whole House Humidifiers Worth It?

There are advantages and disadvantages to whole-home humidifiers. You’ll need to decide if it is worth it for your home. When looking at a property as a new home buyer, I see it as an improvement that won’t hurt you when selling.

A whole-house unit will not only make your home more attractive to potential buyers, but you’ll also reap the benefits of improved air quality, including decreased allergies, chapped lips, dry skin, and creaking wood floors.

As a homeowner, you’re constantly looking for new ways to make your home more appealing. Installing a whole house humidifier is a simple solution with several advantages, as outlined above.

By working with your home’s HVAC system, humidifiers provide optimal moisture levels throughout every room of your home. This allows your family to enjoy a comfortable living environment.

A whole-house humidifier provides the perfect amount of moisture to every room in your home, so you don’t have to worry about dry or wet air.

The humidifier won’t damage your walls or furniture. It’s hard to get moisture in the air, but an HVAC central humidifier will help. Be careful with portable humidifiers because they can cause mold growth if you run them too long or too frequently.


Hubert Miles | Licensed Home Inspector, CMI, CPI

Hubert Miles is a licensed home inspector (RBI# 2556) with more than two decades of experience in inspection and construction. Since 2008, he has been serving South Carolina through his company, Patriot Home Inspections LLC. As a Certified Master Inspector, Hubert is dedicated to providing his expertise in home inspections, repairs, maintenance, and DIY projects.