Indoor House Humidity: Why it Matters
Learn about indoor humidity levels, recommended indoor humidity ranges, and how your HVAC system can help you achieve the ideal home humidity for your family’s health and comfort.
By Anne Fonda
Does your house feel sticky? Do doors and windows stick? Do you get zapped every time you flip a light switch? If you answered “yes” to any of those questions, you may have humidity control problems. Take a crash course on humidity and take control of your comfort.
What is indoor humidity?
Indoor humidity is the amount of moisture (or water vapor) in the air in your home. It’s measured as a percentage. The humidity level may naturally rise in the summer when the outdoor humidity is higher. Similarly, the indoor humidity may fall in the winter months when the air outside is drier and you’re running the heating system.
Ideal indoor humidity levels
What’s the ideal humidity level?
According to the Environmental Protection Agency (EPA), the best home humidity levels will range between 30-50%. Between 30-45% in winter and 40-50% indoor air humidity in the summer is a comfortable humidity level for most people.
Why is this the perfect humidity in my home?
If you can maintain a humidity level in your home within this range, you can prevent the problems that can come with high humidity or low humidity. Keep reading to learn why it’s important to control humidity levels.
Signs of imbalanced indoor humidity
Suboptimal indoor humidity levels can affect how you feel and can cause damage to your home. Here are some signs of high humidity in your home, followed by signs of low humidity.
Signs of high humidity
What is considered high indoor humidity? Officially, anything over 60%. You may start to feel uncomfortable at 55% and notice physical signs of high humidity levels, including:
- Clammy, sticky feeling
- Difficulty sleeping
- Increased asthma and allergy problems
- Musty smell
- Peeling paint
- Interior doors that stick
- Condensation on the walls and inside of windows
- Mold and mildew
- Wood rot
- Increase in dust mites
Mold and dust mites can thrive at 60% humidity and higher. Reducing the humidity will help resolve the issues above and improve indoor air quality.
Signs of low humidity
Low indoor humidity is considered to be anything under 30%. Most homeowners notice signs of low humidity around the 35% range. Signs include:
- Dry eyes
- Dry skin
- Chapped lips
- Dry sinuses
- Nosebleeds
- Sore throat
- Increased static electricity
- Drying, cracking wood
Many of the physical symptoms mentioned above can result from things other than low humidity, so it’s important to find the root cause.
Controlling indoor house humidity
We’re often asked “How can I reduce the humidity in my house?” and there are several answers. Which methods are best for you will depend on the cause of the high humidity and whether it affects your one room, your basement, or your whole house.
Bathroom high humidity
Hot showers and long baths generate a lot of moisture in your bathroom. If you have a bathroom exhaust fan, use it, and leave it running for 20 minutes after the shower or bath. If you don’t have a bathroom fan, consider installing one. In the meantime, open the window to let the humid air out.
Open the bathroom door after you’re dressed to increase ventilation. To prevent mold and mildew growth, you can also use a squeegee on the shower and tub walls and the shower curtain to help excess water and moisture go down the drain rather than evaporate into the air.
Basement high humidity
If you have a damp basement, you also have high humidity. Water intrusion through the walls or floor can cause comfort issues and structural issues. Before you invest in basement finishing or a mechanical solution, you need to address the root of the problem.
By preventing water intrusion through basement waterproofing, for example, you may bring basement humidity levels back within the healthy range. If your basement is still humid, you may want to look into a basement dehumidifier.
Whole house high humidity
If your entire house feels sticky in the summer, it may be an issue with your air conditioner. Central air conditioning units dehumidify as they cool. If the AC unit alone can’t control the humidity you may want to consider upgrading from a single-stage unit to a variable-speed unit with Comfort-R technology for better humidity control.
If you live in a climate that’s humid year-round, such as Shreveport, Miami, or Port Arthur, you may want to look into the benefits of a whole-house dehumidifier. This can help prevent that sticky feeling, musty smell, and reduce the likelihood of mold and mildew growth.
Dealing with low humidity
While high humidity can be limited to one area of your house, low humidity is generally a problem that affects the whole house. If someone has a respiratory illness, a temporary solution to help their dry cough might include using a portable humidifier.
But to increase the humidity level for the whole house, you need a whole-house solution. Whole-home humidifiers add moisture to the air in a cold winter or an arid climate. This increases your comfort level, helps prevent dry skin, and prevents the drying and cracking of wood furniture.
American Standard’s solutions for indoor house humidity
American Standard has two humidity control solutions - a whole-house dehumidifier and our line of whole-house humidifiers (several models to choose from). These humidity control solutions can integrate seamlessly with your HVAC system. Some units also have a standalone installation option.
Let’s take a look.
Whole-house dehumidifier
Our whole-house dehumidifier pulls moisture from the air in your home. If you live in a humid climate or you have a single-stage air conditioner that has a hard time reducing humidity levels, this could be the whole-house solution you’ve been looking for.
A whole-home dehumidifier can remove up to 15 gallons of water a day from the air in your home, greatly reducing the humidity level. Monitor and adjust humidity levels remotely with the American Standard Home App by connecting your dehumidifier to your smart thermostat.
Whole-house humidifier
Whole-house humidifiers are excellent solutions to help increase humidity in your home in the winter. They’re also a great addition to homes in drier climates, such as Nevada, Arizona, and New Mexico.
Bypass humidifiers connect to your furnace or heat pump while our steam humidifier distributes humidified air throughout your home independent of your HVAC system. Speak with your local dealer to determine which solution is best for your home.
Schedule a free quote
Ready to achieve your home’s ideal indoor humidity? Contact your local American Standard dealer for a home assessment and expert product recommendations. Whether you’re in Shreveport battling high humidity or you’re tired of static electricity during a Chicago winter, we can help.
For over 100 years, we’ve designed and manufactured some of the most awarded, well-engineered heating and cooling equipment and earned a reputation for doing things right.
Anne Fonda
Content Writer, Trane Technologies
A Content Writer with Trane Technologies, Anne Fonda researches topics and writes for Trane® and associated residential HVAC brands. She works in collaboration with Trane Technologies subject matter experts, offering easy-to-understand, informative content on complex topics. Her goal is to help consumers make informed decisions on the products and services they need.
She has written for HVAC and other service provider websites for over 16 years. Before transitioning to web content writing, Anne had a 14-year stint as an award-winning journalist. She graduated cum laude from the University of Missouri-Columbia School of Journalism.
When she’s not working, Anne enjoys playing word games, reading, gardening, spending time with family, and visiting gardens and museums.
Expert review by Jennie Bergman Senior Product Manager, Indoor Air Quality
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