Is a Whole-House Humidifier a Good Idea? Pros & Cons

whole-house humidifier

A whole-house humidifier is a system designed to maintain optimal indoor humidity levels throughout your entire home. Like any home improvement decision, there are pros and cons to consider:


  • Improved Comfort: A whole-house humidifier helps maintain comfortable humidity levels in your home, reducing dryness that can lead to issues like dry skin, chapped lips, and irritated respiratory passages.
  • Health Benefits: Proper humidity levels can alleviate respiratory problems, reduce the risk of illnesses, and make it more challenging for viruses to survive in the air.
  • Protects Property: Maintaining the right humidity can prevent wood floors, furniture, and musical instruments from drying out, cracking, or warping due to excessively dry conditions.
  • Energy Efficiency: Properly humidified air feels warmer, allowing you to lower your thermostat in the winter without sacrificing comfort, potentially saving on heating costs.
  • Reduced Static Electricity: Adequate humidity reduces static shocks, which can be especially beneficial for sensitive electronics and preventing discomfort.
  • Less Maintenance: Whole-house humidifiers typically require less maintenance than portable units because they’re integrated into your HVAC system.


  • Installation Costs: Installing a whole-house humidifier can be more expensive upfront, including the cost of equipment and professional installation.
  • Ongoing Maintenance: While maintenance is generally lower compared to portable units, whole-house humidifiers still require regular cleaning, filter changes, and potentially plumbing adjustments.
  • Initial Investment: The cost of a whole-house humidifier may not be justified if you live in a region with naturally humid air.
  • Potential Over-Humidification: If not properly adjusted and monitored, a whole-house humidifier can over-humidify your home, which may cause mold or mildew growth.
  • Compatibility: These systems require an existing forced-air HVAC system and may not be suitable for homes with different heating or cooling setups.

Types of Whole-House Humidifiers

There are 2 types of whole-house humidifiers. These are:

  • Portable whole-house humidifiers
  • HVAC-Installed whole-house humidifiers

As their name imply, portable whole-house humidifiers also called pedestal-style humidifiers can be easily moved from one point to another. They are not connected to the ductwork and are ideal for houses not more than 2500 square feet in size.

portable whole house humidifier

HVAC-installed whole-house humidifiers are connected directly to the HVAC system, specifically just before or after the furnace or air handler. They release moisture in the air which is then supplied to every corner of the house.

Because HVAC-installed whole-house humidifiers are connected to the ductwork, they can be used in big houses unlike portable units which are overwhelmed by size.

These humidifiers are controlled by a humidistat (which looks a like thermostat) and will automatically kick in when the furnace/air handler is turned on. They are more expensive to install but are more effective.

Room Humidifiers vs Whole-House Humidifiers

As I mentioned, room humidifiers are small gadgets which are often placed on top of tables to humidifier the only room they are located in. With these humidifiers, you can see a mist/fog coming out from the top of the unit.

Room humidifiers are used in areas where the air isn’t too dry. Most folks use room humidifiers to humidify the living room or bedroom while the other areas of the house are not humidified.

The advantage of room humidifiers is that they are cheap and are easily transferrable from one room to another. Their disadvantage is the obvious one that they cannot humidify the whole house.

Whole-house humidifiers are more expensive than room humidifiers but can be used to humidify the entire house. Also, they cost more in installation which has to be done by an HVAC professional.

Note: Although humidifiers are used in winter, some people used them during the hot months of summer to cool the house. Humidifiers release moisture in the house which then create a cooling effect as it evaporates.

Just like evaporative coolers, humidifiers can only be used to cool hot and dry areas. Using humidifiers to cool a room in a humid area will only cause an increase in humidity which can then cause mold growth.

Humidifiers vs Location

The choice of whether a whole-house humidifier would be right for your house will most likely depend on location. As you already know, relative humidity is not standard everywhere.

Different areas have different relative humidity levels. Relative humidity is in fact affected by 2 factors which are temperature and location. I will start with temperature.

It is not surprising that relative humidity is defined as the amount of water vapor in the air expressed as a percentage of the total amount that the air can hold at that temperature. An increase in temperature usually results in an increase in relative humidity.

That explains why relative humidity is high in summer compared to other seasons like winter. Hot air has more potential to hold moisture than cold air.

Relative humidity is also affected by location. Some locations have higher relative humidity than others. Areas that are close to large water bodies have high relative humidity levels than areas that are far from water bodies.

Since humidity is basically evaporated water, coastal cities will have more moisture in the air as the water evaporates from the sea. That explains why despite being hot/arid, the average relative humidity in Arizona is 38.5%.

On the other hand, the average relative humidity of Florida is 78.5%. That is because Arizona is far away from water bodies while Florida is almost surrounded by the sea.

During the months of summer, humid states like Florida are so uncomfortable that most homeowners invest in dehumidifiers to remove excess moisture from indoors. Dehumidifiers do the exact opposite of what humidifiers do.

whole-house dehumidifier

On the other hand, folks in areas with low humidity don’t need dehumidifiers. Since the relative humidity there is within the ideal level range, they only need an air conditioner to cool down the air.

Tables turn when winter kicks in. The high humidity levels in humid states drop to within the ideal levels in winters.  Folks in such areas will only need a furnace or heat pump to keep the house warm but will not need a humidifiers.

Note: There are some areas where relative humidity is still high even during winter and may need to continue using a dehumidifier. Just like humidifiers, there are whole-house dehumidifiers and room dehumidifiers.

In winter, the air in arid areas is so dry (low relative humidity) that you cannot comfortable live inside the house without a humidifier. The following are the states with the lowest relative humidity in the United States:

  • Nevada (38.30%)
  • Arizona (38.50%)
  • New Mexico (45.90%)
  • Utah (51.70%)
  • Colorado (54.10%)
  • Wyoming (57.10%)
  • Montana (60.40%)
  • California (61.00%)
  • Idaho (62.40%)
  • Oklahoma (64.00%)

As you can see, if you live in the South Western states you most likely need a whole-house humidifier. On the other hand, folks whole live near large water body will most likely need a whole-house dehumidifier.

Signs You Need a Whole-House Humidifier

The following are the signs that you should consider a whole-house humidifier. They are also the signs/effects of low humidity. When you are experiencing more all of these signs, a whole-house humidifier will be worth its cost.

1. Low Relative Humidity

As I have already mentioned, the ideal indoor humidity is between 30% and 50%. To be more precise, the best indoor humidity in summer is 40-50% while that of winter is 30-40%.

When the relative humidity in your house starts dropping below 30%, there will be negative effects on your health and also in your house. This is especially a concern for folks living in arid areas.

Having said that, I must also add that the ideal indoor humidity also depends on the outside temperature. In some cases, relative humidity levels of less than 30% can be okay if the outside temperature is too low as shown in the chart below.

North AmericaEurope, Australia, New Zealand, Asia, Africa
60 degrees thread angle55 degrees thread angle
sharp crests and rootsrounded crests and roots
tapered threadsparallel threads
Thread sealant neededGasket/O-ring needed for sealing
lower thread density (per inch)higher thread density
bigger pitchsmaller pitch

2. Dry and Itchy Skin

The human body has pores on the skin which helps during perspiration. Also, the skin should stay moist/hydrated at all times.

If the air in the house is too dry, it will pull the moisture from the skin leaving it dry and itchy. The same also happens to the eyes. The eyes are even more at risk as the dryness exposes them to bacterial infections.

If you and members of your family are suffering from dry and itchy skin and eyes then you should install a whole-house dehumidifier.

3. Respiratory Infections

Most viruses are more likely to cause infections when humidity is low than when it is high. That is because the dry air pulls moisture from the virus particles, making them lighter, mobile and therefore easy to get to your respiratory system.

The nose membrane which is always moist will also dry out if relative humidity is too low. As result, the dried out mold spores, dust mite and other allergens will get their way in your air passage and cause allergies to flare up.

Dried out mucous membrane also causes the body to produce mucous to try and counter the effects of dry eyes. Apart from causing nasal congestion, the mucous produced can also cause asthma cases in individuals to worsen.

Another effect of a dried out membrane is nose bleeding. The mucous membrane can crack when picked or blown, resulting in frequent nose bleeds.

If you and/or members of your family are experiencing these signs especially during winter, a whole-house humidifier can help to stop them.

4. Static Electricity

Dry air can cause you to get zapped when you touch objects in the house. That is called static electricity caused by an imbalance between negative and positive charges in a body, usually due to friction, induction or separation.

Since water is a good conductor of electricity, moist air acts as an earth wire and you will therefore never get zapped when relative humidity in the house is high. However, when the air is dry, there will be no way of grounding the charges and that is why you will always be zapped until you install a humidifier.

5. Cracking Wood Products

Dry air sucks moisture from wood and wood products like furniture causing then to shrink and crack. If you are seeing gaps developing between wooden floor planks or cracking furniture then the air in the house is too dry.

Other signs are peeling off paints and artwork or books becoming brittle. You really don’t have to wait for low humidity to damage your possessions and that is why you should install a whole-house humidifier as soon as you realize the area you live in has low relative humidity in winter.

Pros and Cons of Whole-House Humidifiers

whole-house humidifier
whole-house humidifier connected to furnace ductwork

What are the advantages and disadvantages of whole-house humidifiers? Should you even install them?


The following are the benefits of whole-house humidifiers:

1. Automatic Humidity Control

A whole-house humidifier controls your indoor humidity automatically the same way the furnace/heat pump controls the heat. As a matter of fact, the humidifier will start humidifying the air immediately the furnace/heat pump comes on.

Whole-house humidifiers also provide precise humidification. Since they are usually connected to the ductwork, each room in the house is humidified to the desire levels.

2. Improved Health

A humidifier will help prevent the effects of dry air like dry and itchy skin, dry eyes, respiratory infections, allergies, asthma and constant nose bleeding.

3. Wood Products Live Longer

Wood products in the house will no longer lose moisture to the surrounding dry air and will therefore not shrink and crack. Your paint, artwork and other possessions will maintain their shape for a long time.

4. You Stay Warm

Dry air pulls moisture from your skin which exposes you to the elements and as a result you feel cold. Most folks tend to increase the heat more, which not only dries out the air more but it is also expensive.

With ideal humidity levels, moisture on your skin is not lost to the surrounding and you therefore feel warmer.

5. No Need for Manual Refills

Room humidifiers requires the water in the reservoir to be manually refilled frequently. On the other hand, whole-house humidifiers are connected to the house’s water supply and don’t need manual refilling.

6. Adds Home Value

Having a whole-house humidifier will increase the value of your home. It will make it desirable for anyone looking to buy a house as they will be guaranteed of good air quality.


The Following are the disadvantages of whole-house humidifiers:

1. High Initial Cost

Whole-house humidifiers have a high initial cost. Apart from buying the actual humidifier, you also need to pay an HVAC professional to install it for you, which is not cheap.

Installing a whole-house humidifier can cost as much as $1200 or even more. However, considering their benefits, the cost is justifiable.

2. Mold Problem

Mold requires moisture and warmth to grow. A furnace/heat pump provides warmth while a humidifier provides moisture, making your house a perfect bleeding ground for mold, mildew and dust mite.

The reason why humidifiers cause mold growth is poor maintenance. If these units are properly maintained then mold will not have a chance to grow. Changing the evaporator pan filter once a year and the furnace filter once every 3 months is a good way to prevent dust buildup which is a food source for mold.

Wrap Up

And basically that is everything about whole-house humidifiers. I hope that by know you know whether a whole-house humidifier is a good idea for you, or if you should just settle for a room humidifier.