Humidifier Vs Dehumidifier – Which Is Best For Air Quality?

I’m sensitive to both overly dry and humid air. Annoying, I know. That’s why I own both a humidifier and a dehumidifier.

If you’re like me, you might consider buying both units as well. But do you know which device you should use when your home air starts bothering you?

You’re about to find out!

In this guide, I will tell you the differences between humidifiers and dehumidifiers and which unit you should use to maintain healthy indoor humidity levels in your home.

Key Takeaways:

  • Humidifiers add humidity to the living space whereas dehumidifiers do the exact opposite.
  • They can both be beneficial to your health and improve air quality depending on whether you live in a dry or humid environment.
  • For dry weather (humidity < 30%), use a humidifier; for humid weather (humidity > 50%) use a dehumidifier. The key is to maintain 30%-50% humidity.

Humidifiers vs Dehumidifiers – Which Is Ideal for you?

So, you are wondering, “Do I need a humidifier or dehumidifier?” I will help you figure it out.

Here are some cases where one of these devices can help you stay comfortable — alongside my recommendations for which unit you should get.

For Allergies & Congestion – Both Can Work Depending On The Root Cause

Both a dehumidifier and a humidifier can relieve allergies and allergy-induced congestion. You must consider the root cause of your allergies to purchase the right machine.

If your home has high humidity (above 50%), consider using a dehumidifier to reduce allergy symptoms.

Very humid air creates an ideal environment for many allergens to grow and spread.

First of all, dust mites are among the most common allergens — I unfortunately know that very well. These pests love humidity and moisture.

High air humidity creates a perfect environment for dust mites to fill your home.

Additionally, humid indoor air promotes the growth of mold and bacteria.

They can trigger your allergies, so a dehumidifier can help control your symptoms.

Dry air (humidity levels below 30%) can also make allergy symptoms worse by irritating and inflaming your nasal passage, airway, and eyes.

My home getting too dry is even worse for me than excess humidity (if that’s possible).

Humidifiers for allergies can keep you more comfortable by moisturizing your respiratory passages and keeping them from itching. (1)

I recommend checking your home’s relative humidity with a hygrometer and choosing your units accordingly.

For Asthma – Both Can Help Depending on the Cause

I’m asthmatic, and both high and low humidity can be a major contributor to my asthma attacks. That’s why it’s important to keep levels in check.

Dry air can cause your nose and throat to become irritated and trigger asthma symptoms. Humidifiers can be a huge help if you suffer from asthma — they’ve certainly helped me.

But you have to be very careful with a humidifier if you’re asthmatic.

Too much humidity helps mold spores and dust mites grow, which are major contributors to asthma attacks.

Additionally, high indoor humidity makes air heavy and difficult to breathe, which can also worsen your symptoms.

If you use air humidifiers to relieve your asthma symptoms, I once again encourage you to buy a hygrometer or a device with a built-in humidistat to help you check that you’re keeping indoor humidity within the healthy 30-50% range.

For a Stuffy Nose & Cough – Get a Humidifier

If you have a stuffy nose and cough, a humidifier can help you in most situations.

Too-dry air dries out your airway and increases mucus production, which only makes your nose more clogged up.

My wife is very happy with our humidifier because it keeps me from coughing all day long.

Humidifiers can also help you if your stuffy nose and cough are due to a cold.

Not only does good indoor air humidity make it easier for you to breathe, but it can also destroy airborne viruses.

With fewer viral particles in the air, you and your family are less likely to get sick. (2)

Once again, though, make sure you don’t increase the humidity level too much (above 50%) since it can make some disease-causing bacteria and viruses grow out of hand.

Learn More: Best Humidifiers for Sinus Problems

For Dry Skin – A Humidifier Can Help

Needless to say, very dry air can dry out your skin and make it unbearably itchy.

A humidifier can help with dry skin — and avoid you having to slather yourself with moisturizer every five minutes.

Adding moisture to indoor air prevents your skin from drying out as fast. As a result, you can enjoy your home life without itching and cracked skin.

Additionally, Humidifiers can relieve eczema, psoriasis, and other skin conditions.

They can’t cure these ailments, but they help moisturize the skin and reduce itchiness, particularly during dry months and winter.

For Snoring & Sleep Apnea – Generally Humidifiers Can Help

I snore and that impacts both mine and my wife’s sleep. Many things can make you snore, from dry mouth to allergies, asthma (as in my case), and more.

A humidifier in your bedroom can relieve these symptoms. To improve sleep, humidifiers can keep you from snoring too.

Humidifiers can also provide relief for sleep apnea, a difficult breathing condition.

They won’t cure you, but moist indoor air can help you breathe easier and prevent sleep apnea symptoms. (3)

However, your bedsheets can be a paradise for dust mites — especially if you live in a humid environment.

If air moisture in your bedroom is high, a dehumidifier can help keep the allergy-inducing pests in check.

For Baby/Nursery – Both Can Be Helpful

For your baby’s room or nursery, you’ll probably want to opt for a humidifier.

Unless your baby is sleeping in the basement or your home doesn’t have air conditioning, you likely aren’t going to need a dehumidifier.

Air that’s too dry can make your child more susceptible to cold viruses and other illnesses. You need a humidifier to combat that risk.

If your little one suffers from allergies or asthma, though, too humid air could make these symptoms worse.

You surely want only the best for your child — I know I do — so it’s a smart move to invest in a reliable hygrometer.

Measure humidity in the nursery and buy a humidifier or a dehumidifier according to the results.

Read More: Where To Put Humidifier in a Nursery

Costs – Both Can Be Found in Varying Budget Ranges

On top of health benefits, costs are a big consideration with humidifiers and dehumidifiers.

I have good news for you — you can find a device to match your budget, whether you need a humidifier or a dehumidifier.

Both dehumidifiers and humidifiers are available at a massive range of prices.

The lower-end models won’t have all the bells and whistles and may not function as effectively as more expensive ones, but they can still provide relief to your situation.

My first humidifier was a cheap $20 model and even that helped me a lot.

When it comes to running costs, both types of devices need electricity. A dehumidifier will likely result in a bigger energy bill than a humidifier.

The Environmental Protection Agency says humidifiers are only responsible for roughly 0.11% of annual U.S. household energy consumption. (4)

The total energy consumption depends on the type of humidifier or dehumidifier, though.

I suggest looking for machines with Energy Star or other energy-efficiency certificates.

Maintenance – Both Require Regular Maintenance

Whether you run a humidifier or a dehumidifier, the story is the same when it comes to maintenance. I can’t overstate how important regular cleaning is to avoid introducing mold or bacteria into your home.

With humidifiers, you must clean the water tank every day. You should also use distilled water in the device to prevent mineral buildup on its parts.

Dehumidifiers, too, require daily water tank cleaning to keep them from getting moldy.

You should regularly check their cooling coil for frost, as an icy coil reduces the dehumidifier’s effectiveness (I’ll get to this later, so keep reading!).

Cleaning the Air – Both Do Not Clean the Air

Many people try to make comparisons between an air purifier vs. a humidifier vs. a dehumidifier.

I say, don’t bother comparing them — humidifiers and dehumidifiers do not clean indoor air. They’re only good for removing or adding moisture to it.

If you want to clean allergens, pollutants, and impurities from indoor air, use an air purifier.

You can run an air purifier together with a humidifier or dehumidifier to help you breathe easier with cleaner air — that’s what I do.

Related Article: Humidifiers vs Air Purifiers Explained

What Exactly Does a Humidifier Do? (Types Explained)

A humidifier adds moisture to the air to boost the humidity in your home, office, or any other indoor space.

There are different sizes and types of humidifiers — from tiny portable ones to whole-house humidifiers — which use different methods in order to create moisture.

I know it can get confusing, so here’s my breakdown of the major types of humidifiers.

Warm Mist Humidifiers

Warm mist humidifiers add moisture to the air by boiling water and releasing steam that is slightly cooled before exiting the humidifier.

As they produce a warm mist, they can be particularly soothing for people suffering from respiratory conditions.

However, you need to be careful with these units to avoid burning yourself, your children, or your pets.

Cool Mist Humidifiers

Cool mist humidifiers don’t have a heating element — the mist or water vapor starts and stays cold, hence the name.

Some cool humidifiers use a disc spinning at high speeds or an intensely vibrating plate to create tiny droplets of water that are pushed into the air. Others use air blown over a wet wick to push out moist air.

Ultrasonic Humidifiers

Ultrasonic humidifiers are a type of cool mist humidifier — and they’re my favorites.

They create a fine mist through the super-fast vibrations of a plate called the diaphragm.

An ultrasonic device can be a very energy-efficient and affordable method for adding moisture to your home.

Evaporative Humidifiers

Evaporative humidifiers are also cool mist humidifiers, but they rely on simple evaporation to moisturize the air.

They suck water into a wicking filter, from which a fan blows it into the room.

Natural evaporative humidifiers don’t use a fan at all — they simply allow the water to evaporate on its own.

If you’re as energy-conscious as I am and don’t need a high-powered humidifier, these evaporative humidifiers can be best for you.

Related Article: Differences Between Evaporative and Ultrasonic Humidifiers Explained

Pros & Cons of Humidifiers In The Home

What I Like
  • Reduced risk of contracting cold and flu viruses
  • Healthier potted plants and furniture
  • Less dry skin, chapped lips, nosebleeds, etc.
  • Can save money and energy during cold weather
  • Reduced static electricity, which can make you more comfortable and help eliminate the risk of damage to electronics
What I Don’t Like
  • Requires regular cleaning to avoid harmful bacteria and mold
  • Produces noise which can be potentially annoying
  • If unsupervised, can produce too much moisture

Then What Does a Dehumidifier Do?

You can guess it by the name — a dehumidifier removes moisture from the air.

If your home feels musty or damp, these machines are awesome for drying your living spaces.

Most models are able to reduce high humidity levels all the way to the ideal 30-50%.

They function in different ways and come in varying sizes from small, portable units to large whole-house dehumidifiers.

Compressor dehumidifiers Are the Most Popular

Compressor dehumidifiers are the most popular units (and what I use). They use condensation to draw water out of the environment.

Once the damp air is taken in, it travels over a cold coil, where the water condensates on the coil’s surface.

From there, the condensed moisture drips into a tank or reservoir.

The dry, cold air is warmed to room temperature and released into the area around the unit.

You should empty the water tank each time it fills, at least once a day. I didn’t realize that with my first unit and ended up with so much mopping.

Desiccant dehumidifiers Are Less Effective but Low-maintenance

Desiccant dehumidifiers operate more like a sponge. A compressor draws moist air into the device, where it’s blown over a desiccant wheel that absorbs the moisture.

The dehumidifier then blows the dry air back into the room.

The now-damp desiccant wheel is dried by an internal heater. As such, there’s no water tank to empty, which reduces the amount of maintenance you have to do.

The desiccant wheel can last for years before it needs replacement.

Desiccant humidifiers also produce little to no sound and are more compact, making them more convenient.

However, they are less effective and can struggle to dehumidify large rooms.

Learn More: Types of Dehumidifiers Explained

Pros & Cons of Dehumidifiers

What I Like
  • Helps with allergies by reducing the risk of mold and dust mite growth
  • Increased comfort levels
  • Helps minimize skin irritation and respiratory issues
  • Clothes dry quicker and stored food is less likely to get moldy
  • Desiccant dehumidifiers are compact and low-maintenance
What I Don’t Like
  • Compressor dehumidifiers are quite noisy
  • Can increase the energy bill
  • Requires regular maintenance as the storage tanks must be emptied and cleaned out often (with compressor dehumidifiers)

Common Questions About Humidity (FAQ)

Can you run a humidifier and a dehumidifier at the same time?

You can run a humidifier and a dehumidifier simultaneously, but you should place them strategically in different parts of your home.

Having both in the same room is counterproductive in most cases.

Can a dehumidifier be used as a humidifier?

No, a dehumidifier can’t be used as a humidifier. The devices serve the exact opposite purposes.

Dehumidifiers only remove moisture from the air, making the air dryer.

How do you know if you need a humidifier in your room?

You can tell that you need a humidifier in your room by common, telltale signs of dry indoor air. These include:

  • Excessive static electricity
  • Dry or itchy skin
  • Nosebleeds
  • Chapped/cracked lips
  • Frequent coughing
  • Allergies and worsened allergy symptoms
  • Congestion
  • Gaps and crack in wood flooring and furniture
Do dehumidifiers kill viruses?

Dehumidifiers don’t kill viruses, but they can make your home less hospitable to viruses by lowering overly high relative air humidity.

High humidity helps viruses survive, so removing excess moisture can lower the levels of viral particles.

Wrapping the Comparison up

That’s pretty much everything there is to know about the differences between a humidifier vs. dehumidifier.

Have you decided which one is right for you and your needs? I hope I’ve made that a very easy decision for you.

Using humidifiers and dehumidifiers in the right situation has greatly improved my home’s indoor air quality.

You, too, are now well on your way to breathing easier and living more comfortably!



Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.