Ideal Humidity Level for Your Home

May 22, 2024
A hygrometer with the humidity levels of a room.

You want your home to be comfortable, but that doesn’t mean it shouldn’t have any humidity. The perfect balance ensures your home feels comfortable and doesn’t risk mold growth or a damaged structure. 

Proper humidity levels are also good for your overall health because it is easier to breathe and generally function in pleasant humidity levels. Ideally, your home should have 30 – 50% humidity. 

High humidity can create mold and mildew grow, which is bad for your health and makes your home feel stuffy. Low humidity can make you feel dry all over, including your skin and throat.

High and low humidity can also put your home at risk of unnecessary damage, including mold and mildew growth and structure cracking or shrinking.

Table of Contents

Understanding Humidity

Humidity is the amount of water vapor in the air. There are two measures of humidity – absolute and relative.

Absolute humidity is the exact measurement of water vapor in the air. Relative humidity calculates the amount of water vapor in the air but compares it to the current temperature. 

Warm air has more water vapor than cold, so relative humidity levels are higher in cold air than in warm air with the same amount of humidity.

Causes for High Humidity

If the air in your home feels unbearably ‘heavy,’ almost like you’re living in a sauna, there could be many reasons, including:

  • Home activities: Taking showers, cooking, and washing clothes all add moisture to the air. Some of this water may evaporate and contribute to the home’s humidity.
  • Bad ventilation: Proper exhaust fans in bathrooms and kitchens absorb the excess moisture created when bathing or cooking. If there is poor ventilation, the humidity levels increase.
  • Pipe leaks: Leaking pipes put excess moisture in the air and increase the humidity levels.
  • Roof leaks: Roofing is the most important protection for your home; a small leak can increase humidity levels if rain or snow gets into the home, no matter how small the leak.
  • Inefficient HVAC system: If your HVAC system isn’t up to the job, it may not keep your home cool enough, and humidity levels will increase. The same is true if your AC unit is too large for your house. If an AC unit cools the air too quickly, it will not remove enough moisture and could cause problems.

Effects of High Home Humidity in Your Home

High humidity in your home can have many negative effects, including the following:

  • Mold growth: All homes have some level of mold, but if those mold spores have damp, dark places to grow, they can quickly multiply. Mold can cause health problems in children, the elderly, and the immunocompromised.
  • Damaged walls: Condensation often settles on walls, causing paint and wallpaper to peel. It can also cause staining or even water damage, weakening the drywall.
  • Rotted floors: Humidity can cause your floors to become weakened, have mold growth, and begin to buckle, especially if you have wood floors.
  • Poor human health: High humidity can also harm your overall health. It can cause dehydration, heat exhaustion, cramps, and even fainting.

Signs of Excess Humidity in the House

  • Condensation on windows and mirrors
  • Peeling paint or wallpaper
  • Water stains on the ceiling
  • Mold growth
  • House smells musty

Effects of Low Humidity

Your home could easily have low humidity levels during winter because the outdoor air is much less humid in winter than in summer. This can cause many issues with your health and home.

How Low Humidity Affects Your Health

  • Dry skin
  • Itchy eyes
  • Dry, scratchy throat
  • Dry sinuses
  • Dry, cracked, and chapped lips
  • Viruses spread faster throughout the house
  • Causes respiratory issues for anyone with asthma or allergies

How Low Humidity Affects Your House

Your home’s structure needs the perfect amount of moisture. If there is too much moisture, you may experience rotting or mold growth. 

However, insufficient moisture can dry wood out too much, causing it to crack, split, and shrink. The damages caused cannot be reversed and must be completely remediated.

Signs of Low Humidity in the House

  • The house feels cold even after turning the heat up
  • The electrostatic discharge in the house is excessive
  • Everyone complains of feeling dry, either throats, sinuses, or skin

Finding the Ideal Humidity Level

Everyone will have a different humidity level they find comfortable, but overall, consider the following humidity levels:

  • Summer: Keep humidity levels at 40 – 50% in the summer. Anything above 60% will make the house feel muggy and uncomfortable.
  • Winter: Keep humidity levels at 30 – 40% in the winter. If you make the humidity levels any higher, it can cause condensation and water damage.

Of course, you should consider personal preferences and when you feel the best. The recommended humidity levels ensure your home’s health, but each person has different personal preferences and needs depending on their health.

Tools for Measuring Home Humidity

You’re probably wondering how to tell your home’s humidity levels. You can invest in a simple tool called a hygrometer that works like a thermometer to monitor your home’s humidity levels.

If you don’t have one, you can also try the water test:

  1. Get a glass of water and two to three ice cubes. 
  2. Place the glass on a counter, put the ice cubes in it, and return after four minutes. 

If the glass has condensation, your humidity levels are too high, but if there is no condensation, your humidity levels may be too low.

Of course, this test isn’t foolproof. It depends on the outdoor temperatures and the indoor activities. 

For example, if someone just ran the shower or you did a load of laundry recently, the humidity levels may be elevated temporarily. Try to run the test when everything in your house is calm for the most accurate results.

Benefits of Maintaining Ideal Humidity

Keeping an eye on your home’s humidity level has many benefits, including:

  • Improved air quality: With ideal humidity levels, there’s less concern for mold growth or difficulty breathing.
  • Enhanced comfort and well-being: When humidity levels are stable, it’s easier to breathe, viruses don’t spread as easily, and anyone with a compromised immune system or respiratory allergies may breathe better.
  • Prevents mold growth: Excessive humidity can create a breeding ground for mold growth, harming your house and the health of your household members, especially anyone with chronic health issues.
  • Protects home’s structure: High humidity levels can cause water damage, stained walls, and peeling paint. They can also cause moisture to accumulate on furnishings, making them less stable. Low humidity levels do the opposite and make your home’s structure dry and brittle, which can cause cracked or split wood.

Monitoring and Controlling Humidity

It can be difficult to achieve the ideal humidity in your home, but here are some quick DIY steps you can take to help.

Increase Humidity Levels

  • Add houseplants: Having plants indoors can increase your home’s humidity level from the leaves and stems’ vapors with proper watering. Stick with tropical plants that thrive in dry conditions for the best results.
  • Skip the dryer: Hang dry your laundry to naturally increase your home’s humidity. As the laundry dries, the water evaporates into the air, increasing your humidity levels.
  • Take advantage of shower steam: Open the door and let the steam travel through the house after showering. Don’t turn on the bathroom’s exhaust fan; this will eliminate the steam.
  • Install a humidifier: The easiest way to control your home’s humidity is to purchase a humidifier. You can have one professionally installed on your furnace to control the entire home’s humidity or individual units for humidity control in a single room.
  • Check for leaks: If your windows or doors leak, they release moisture and decrease humidity. Install weatherstripping and repair any leaks from windows or doors to control your home’s humidity levels.

Decrease Humidity Levels

  • Use exhaust fans: Fans in your kitchen and bathroom remove the excess moisture from showering or cooking, send it outdoors, and decrease your home’s humidity levels.
  • Fix leaks: If your roof, doors, windows, or pipes leak water, the excess water will increase your home’s humidity levels. Have leaks fixed immediately, and consider waterproofing if it keeps happening.
  • Monitor carpeting: If you have carpeting throughout the house or even in a room, check for moisture. Carpet fibers absorb moisture, which can grow mold and increase humidity levels. Area rugs are best because they can be washed and dried without concern.
  • Ventilate crawlspaces: Ensure crawlspaces have plenty of ventilation, and consider placing a vapor barrier or plastic over the soil to stop moisture from seeping through and creating humidity.
  • Use a dehumidifier: If your house has too much humidity, consider using a dehumidifier in those rooms to decrease the moisture.

Conclusion

Finding the ideal humidity level for your house is the key to good health and a comfortable home. High humidity levels can cause mold growth and water damage, and low humidity levels put your house at risk of cracking or shrinking, not to mention the toll it takes on your overall health.

FAQs

Is 70% humidity in a house too high?

It’s best to keep your home’s humidity levels between 30% and 50%. If they get any higher, you put your home at risk of mold growth, which can damage your walls, ceilings, and even furniture.

How do you get rid of high humidity in your house?

The best way to eliminate excessive humidity in your house is to use a dehumidifier in the rooms with excessive moisture. Other options include always using exhaust fans in bathrooms and kitchens (when cooking), fixing leaks because accumulated water creates humidity, and properly ventilating your crawlspace.

What is causing high humidity in my house?

Oftentimes, accumulated water causes high humidity in your house. Other causes could be using an AC unit that’s too large for your home size, not using exhaust fans properly, or bad ventilation.

What happens if the humidity is too high in a house?

When humidity is too high in a house, it can cause water damage. You may find water stains on walls and ceilings, mold growth in dark, damp areas, peeling paint or wallpaper, or a musty smell in the house.

Will 70% humidity cause mold?

It’s impossible to say what humidity level will cause mold, but any excessive moisture in the air risks mold growth. To reduce the risk of mold, it’s best to keep your humidity levels at 30 – 50%.

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