How to Maintain Proper Humidity Levels in Your Home

Excess Moisture Can Promote Mildew and Bacteria Growth

Close-up view of residential kitchen

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Keeping the correct humidity level in your home is important to your well-being as well as that of your house. While a little moisture can be beneficial, too much could be hazardous to your health by promoting bacteria growth. It can also do damage to the home and your possessions, especially if gone unchecked for long periods of time. Fortunately, humidifiers and dehumidifiers can help you control the humidity in your home.

Recommended Humidity Levels

The recommended average relative humidity level is between 35 percent and 45 percent. This range will provide the best comfort for your family. It also helps to protect your musical instruments, drywall, wooden furniture, and other belongings or materials from the damaging effects of dryness or excessive moisture.

Relative humidity levels fluctuate depending on climate and air temperature. It's important to use the suggested average with caution and apply it along with knowledge about your own home. How a house handles humidity depends on many factors including how airtight the building is, its design and construction, and any vapor retarders that are installed.

Measure Humidity With a Hygrometer

A hygrometer can be used to help you measure the relative humidity in your home so you can maintain an optimum level. It is a small instrument with a display that shows what the relative humidity level is in the room.

Inexpensive and user-friendly, this little gadget can help you monitor the air so you can adjust your humidity level when needed. That can be achieved by adding either a humidifier or dehumidifier (or both) to your home. Since humidity changes with the seasons, you will want to monitor it and make adjustments regularly.

The Effects of High Humidity

When there is too much moisture in your home, moist air gets trapped in corners, basements, and other closed areas. This is often very noticeable in bathrooms when moisture gathers in corners and creates mildew that is difficult to remove. Condensation can also accumulate in windows, causing water to drip down the window, and wooden frames to rot. Also, if you notice a musty odor, it is a sign that you need a dehumidifier in your home.


This excess moisture in the air provides a perfect breeding ground for bacteria. It can also damage things that are sensitive to moisture, such as wood, paper, fabrics, and major mechanical systems like your heating, ventilation, and air conditioning, or even the toilets and pipes.

How to Remove Humidity

What method you choose to remove moisture from the air depends on the severity of the problem, the season, and where the dampness is.

  • If it is winter and an area such as a basement could benefit from heat, heating that space could return it to a proper moisture level. If the humidity is excessive, you may need a combination of both heat and a dehumidifier to reach proper levels.
  • A damp bathroom can benefit from an open window or a ceiling exhaust fan to draw the moist air or steam from showers and baths to the exterior of the home.
  • In spring when heating is not an option, buying a dehumidifier may be your best option for removing dampness from the basement or main floor.

Portable Multi-Function Units

Air conditioners also help control moisture levels in your home. Some portable humidifiers are designed with adjustable built-in monitors that activate the unit when levels are too low or turn it off when levels are too high. If you think these portable units might help, consider buying a multi-function unit for your home that will also act as an air conditioner.

When to Add Humidity

During cold winters, your heating system can make the air in your home too dry. This can cause discomfort, dry skin, and wooden items to crack. To improve the air quality, you can add a humidifier to those areas where you spend the most time. Some people benefit from having them in the bedroom to humidify the air overnight. Another option is to install a whole-house humidifier to your heating system.

Product Care and Maintenance

If you are using a humidifier or dehumidifier, take the time to read your product manual. To get the most efficient use out of it and ensure its longevity, you will want to follow the recommended guidelines for filter changes and cleaning. If your product is running with a clogged and dirty filter, you could be adding bacteria and mold spores to the room. Regular cleaning and filter changes will prevent this.