Maintaining proper humidity levels in your home is important for comfort and health. Low humidity can cause dry skin, cracked lips, static electricity, and damage to wooden furniture and flooring. High humidity encourages mold growth, dust mites, and makes the air feel muggy. Most homes need dehumidification in summer and humidification in winter to keep humidity within the 30-50% recommended range.
Signs your home needs a dehumidifier
Here are some signs that your home’s humidity may be too high and would benefit from a dehumidifier:
- Condensation on windows and other surfaces. If you see water droplets forming on cold surfaces, that’s excess moisture in the air condensing out.
- Musty odor. If your home smells damp and moldy, high humidity is likely the cause.
- Peeling paint or wallpaper. When moisture gets behind wall materials, it can cause them to peel or bubble.
- Mold growth. Excess moisture encourages mold to grow on walls, ceilings, basement corners, and HVAC equipment.
- Stuffy air. High humidity makes the air feel heavy and uncomfortable to breathe.
- Allergies or asthma flaring up. Mold spores and dust mites thrive in humid environs and can aggravate respiratory issues.
- Wood furniture warping. As wood absorbs moisture from the air, it swells and begins to warp or crack.
- Floor buckling. Excess moisture causes wooden floors to swell at the seams and lift up.
- Electronics or metal objects rusting. Moisture in the air causes corrosion on electronics and metal fixtures.
- High humidity readings. If a hygrometer shows relative humidity consistently above 60% in your home, a dehumidifier is recommended.
If you’re experiencing several of these humidity issues, a dehumidifier can likely resolve them by extracting excess moisture from the indoor air.
Signs your home needs a humidifier
Here are indicators that the air in your home may be too dry and would benefit from a humidifier:
- Dry, itchy skin and cracked lips. Low moisture robs skin of water and causes irritation.
- Static electricity shocks. Dry air prevents static charge from dissipating, leading to zaps when you touch metal or grounded objects.
- Dry, scratchy throat and sinuses. Humid air keeps respiratory tissues moist and healthy.
- Nosebleeds. The mucous membranes in the nose dry out and crack, causing nosebleeds.
- Dry, crumbly nasal passages. Breathing overly dry air dehydrates nasal passages and makes mucous membranes parched.
- Scratchy, irritated eyes. Humidity helps keep eyes moist and comfortable.
- Cracked furniture. Wooden furniture, especially antiques, can shrink and crack when the air is too dry.
- Peeling wallpaper. Low moisture causes the paper to contract and pull away from the wall.
- Warped flooring. Wooden floors shrink and buckle when deprived of moisture.
- Low humidity readings. If a hygrometer shows relative humidity below 30% inside your home, a humidifier can help raise it.
Experiencing multiple dry air problems in your home is a clear sign that a humidifier is needed to boost moisture levels and achieve comfort.
Ideal humidity range for homes
The recommended indoor relative humidity range is 30-50%, according to the EPA and American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). At humidity levels in this range:
- Indoor air feels comfortable for most people.
- Respiratory infections are less likely to spread and impact health.
- Dust mites and mold growth are inhibited.
- Wood furniture and flooring are protected.
- Paint and wallpaper are less likely to peel.
- Skin, throat, eyes, and nasal passages stay moist and healthy.
Aim to keep your home’s humidity between 30-50% year-round. A hygrometer is recommended to monitor humidity inside your home.
Using a dehumidifier to lower humidity
A dehumidifier removes excess moisture from indoor air and reduces relative humidity. It draws air in, condenses water vapor from the air by cooling it below dew point, collects the condensate in a tank, and discharges dry air back into the room. Key tips for using a dehumidifier effectively include:
- Size it properly – Choose a dehumidifier rated for the square footage of the area you want to treat. An undersized unit won’t provide enough drying capacity.
- Set the humidity level – Adjust the unit’s humidistat to your target humidity, typically 50% or lower. The dehumidifier will run until it reaches this setting.
- Drain the tank – When the condensate tank fills up, the unit will shut off automatically. Drain the tank so it can keep running.
- Clean the filter – For maximum airflow and efficiency, clean the air filter monthly.
- Supplement with A/C – Run your air conditioner and dehumidifier together to lower humidity more effectively.
- Use a hygrometer – Use a humidity gauge to monitor indoor humidity and see if further adjustments are needed.
With proper setup and maintenance, a dehumidifier can keep your indoor air comfortably below 60% relative humidity.
Tips for lowering whole house humidity
For excessive moisture across your whole house, try these tips in addition to using a portable dehumidifier:
- Run a whole house dehumidifier – Have a HVAC contractor install a dehumidifier in your ductwork to condition the entire home.
- Increase A/C runtime – Lower your A/C’s thermostat to run it longer and remove more moisture.
- Seal damp areas – Use caulk, expanding foam, and weatherstripping to seal moist crawl spaces, basements, attics and faulty windows.
- Ventilate – Open windows when humidity is lower outside. Run bath and kitchen exhaust fans longer.
- Drain gutters – Make sure gutters are clean and draining properly so moisture doesn’t saturate the ground near your foundation.
- Fix plumbing leaks – Detect and repair any leaky pipes, faucets and seals that allow water into your home’s structure.
Targeting excess moisture across all living spaces provides whole house humidity relief.
Using a humidifier to raise humidity
There are several types of humidifiers that can raise low indoor relative humidity:
- Warm mist humidifiers boil water to produce steam that is released into the air. The steam humidifies and slightly warms room air.
- Cool mist humidifiers rely on fans and moving air to evaporate and disperse water as a fine mist. They don’t heat the water so don’t warm your space.
- Ultrasonic humidifiers vibrate at high frequencies to create microscopic water droplets that humidify the air very efficiently.
- Evaporative humidifiers draw air through a wet wick filter to add moisture to the airstream before releasing it back into the room.
Key tips for successfully using a humidifier include:
- Choose an appropriate type and size for your environment.
- Change and clean the water daily to limit bacteria and mineral buildup.
- Use cool boiled or distilled water to minimize white dust.
- Set the humidistat to your target humidity, around 40-50% typically.
- Run it continuously to maintain humidity.
- Keep it on a waterproof surface in case of leaks.
- Monitor humidity with a hygrometer and adjust output as needed.
Proper humidifier use can boost indoor relative humidity to comfortable levels within your targeted range.
Tips for whole house humidification
For very dry air throughout your home, consider these supplemental tips along with running portable humidifiers:
- Install a whole home humidifier on your HVAC system to treat all living spaces.
- Group multiple portable humidifiers throughout your residence.
- Run your HVAC fan longer to circulate air through the humidifier more.
- Seal gaps and cracks where heated indoor air can escape to the outside.
- Open indoor windows only when the outside humidity is higher.
- Use room vaporizers and humidifying plants.
- Set your indoor thermostat lower so your heating system runs longer.
A coordinated effort combining multiple methods is best for countering very dry air in an entire house.
Ideal times to use a dehumidifier or humidifier
Because outdoor conditions drive indoor humidity levels, the times of year when dehumidifiers and humidifiers are most needed differ:
Use a dehumidifier in:
- Summer – Hot, humid weather causes high indoor moisture.
- Monsoon season in wet climates – Frequent rain saturates the air.
- Basements year-round – Ground moisture permeates basements.
- Coastal regions in warmer months – Moist ocean air raises humidity.
Use a humidifier in:
- Winter – Heating dries the air in cold weather.
- Arid climates year-round – Dry outside air dehydrates indoor air.
- At high elevations – Low atmospheric pressure results in dry air.
- In arctic regions – Extreme cold desiccates the air.
Knowing your local climate patterns helps determine when you’ll get the most benefit from dehumidification or humidification.
Measuring and monitoring humidity
To control indoor humidity effectively, you need to measure and monitor it. Here are some options:
Hygrometers
A hygrometer is a humidity gauge that displays the current relative humidity percentage in your home. Models include:
- Digital hygrometers – Provide an LCD humidity readout and some include thermometers to measure temperature too. Prices range from $10-50.
- Weather station hygrometers – Offer humidity measurement along with other weather data like rainfall and wind direction. Prices range from $30 for basic models to over $200 for those with wireless remote sensors.
- Humidity pens – These analog dial hygrometers are inexpensive at $2-10 but not the most accurate option.
- Psychrometers – Use wet and dry bulb thermometers to take a manual measurement of relative humidity. They cost around $20-100.
Digital hygrometers provide the easiest to use and most accurate humidity measurements.
Smart home devices
Many smart home devices display and record humidity readings:
- Smart thermostats like Ecobee and Nest Learning Thermostat.
- Smart speakers with displays like Amazon Echo Show.
- Home weather stations like Netatmo, AcuRite, and Ambient Weather.
- Smart TV boxes like Apple TV display humidity on your TV if you ask their voice assistant.
These let you monitor indoor humidity remotely using your smartphone and some can provide historical data. Convenience comes at a cost though, with most models ranging from $100-250.
Humidity monitors
For whole home humidity tracking, monitor systems with multiple sensors connected to a central control panel are available. Popular options are:
- Sensaphone – Monitors humidity in up to 4 locations and sends alerts for high or low readings. Around $600.
- Airthings – Displays and records humidity and temperature throughout your home via wireless sensors. Prices start at $199.
- Ambient Weather – Measures humidity in up to 8 zones with remote sensors that communicate wirelessly. Around $350 for a starter kit.
These systems provide 24/7 tracking of humidity across large homes but are an investment.
Smart HVAC systems
Many modern smart thermostats and HVAC systems monitor humidity at their control panels and in remote sensors. Brands like Carrier, Trane, ecobee, and Emerson include humidity tracking in high-end equipment. This integrates humidity measurement into your overall home comfort system.
Humidity recommendations by room
Ideal humidity ranges may vary slightly by room depending on their use:
Living Spaces
Bedrooms, living rooms, family rooms, etc. – 40-50% humidity.
Bathrooms
Full baths with showers – 50-60% humidity.
Half baths – 40-50% humidity.
Basements
Finished basements – 40-50% humidity.
Unfinished basements – Less than 60% humidity.
Attics
Vented attics – Balanced with outside air.
Unvented attics – 40-50% humidity.
Garages
Attached garages – 45-55% humidity.
Detached garages – Balanced with outside air.
Aim for these target humidity ranges in each room type for optimal comfort and moisture control.
Conclusion
Maintaining proper humidity in your home requires careful monitoring and the right equipment for your conditions. Pay attention to signs of low or high humidity and use hygrometers to track your indoor levels. Address excess moisture with dehumidifiers in summer and times of high outdoor humidity. Combat dryness in winter with humidifiers. With the right balance of dehumidification and humidification for your climate, you can achieve the 30-50% ideal humidity range for comfort and health all year long.