How to Control Humidity in Your Home

Hot, humid air isn’t just uncomfortable, it’s also unhealthy. Find out how to lower your home’s humidity without draining your bank account.

Heading to higher ground to catch a cool breeze and sitting in the shade while sipping lemonade are old-fashioned ways to handle a hot and humid day, but they’re not very effective. 

Humidity isn’t just annoying, it’s also dangerous, especially if you live in a consistently humid city like so many in the South, including Texas, Louisiana, Florida, Mississippi, Arkansas and Alabama. This “red zone” is where  many of the most humid cities in the U.S. are located. It’s also seeing longer periods of extreme heat each year.

Hot, humid air can cause asthma symptoms, according to the asthma & allergy friendly certification program jointly run by the Asthma and Allergy Foundation (AAFA) of America and Allergy Standards Limited, because it helps common allergens such as dust mites thrive. Air pollution, ozone and pollen levels go up in hot and humid weather. Those increased particles in the air can aggravate sensitive airways. In addition, humidity encourages mold growth, which can cause illness.

Focus on Rooms With High Moisture Levels

Ideally, the humidity in your home should be between 35% and 40%, according to Kenneth Mendez, CEO and president of AAFA, or at least under 50%. That’s a hard number to reach in summer months in the South, but you might get close.

“It’s especially important to improve ventilation in rooms that have more moisture, such as kitchens and bathrooms,” says Mendez.

An automatic humidity sensor can help you keep an eye on humidity levels in your home. A bathroom fan with an automatic sensor can cost from $70 to $300 uninstalled. 

“You should also be attentive to leaks and floods that may spur mold growth,” Mendez adds. 

Any time you improve the relative humidity in your home, you make it less convivial to mold and dust mites.

Another suggestion from Bailey Carson, a home care expert at Angi: Try showering in cooler water, and fling open your doors and windows on drier days for ventilation. Let the outside in. (Although, it should be noted that this idea is less useful in the Southeast, where outdoor humidity is well above the comfort level half the year).

“Clean your air conditioning filters regularly,” Mendez says. “Use portable air purifiers throughout your home, especially in the bedroom. And keep your home clean to further reduce mold. Dust and wipe down solid surface flooring with a damp mop regularly. Use a vacuum cleaner with a HEPA-filter frequently, and you can avoid most mold and humidity allergen triggers in your house."

To keep the humid air out of your home in the first place, make sure that your doors and windows are properly sealed, Carson recommends. 

Compare Dehumidifiers

Whether you have one room that's particularly susceptible to humidity or it affects your entire home, a dehumidifier is typically the go-to solution. Not all dehumidifiers are created equal, however. Some are much more energy efficient at doing the same amount of work.

Running a dehumidifier will cost $.83 to $3.54 per day, according to Eco Cost Savings. An energy efficient dehumidifier costs up to $1.97 per day.

The table below is viewed best horizontally on mobile devices.

Source: Eco Cost Savings

“Most people prefer a home humidity level between 40% and 60%,” says Lane Dixon, vice president of operations for Aire Serv, a Neighborly company.  “For homes that have higher humidity levels, it’s good to set up dehumidifiers in the home. They take the moisture out of the air, helping to lower or reduce the humidity level.”  

The problem is that a dehumidifier can suck up a lot of energy and lead to higher utility bills. But there are options that reduce demand on the electric grid. While all dehumidifiers need to use energy to run, there are some versions that are more energy efficient than others, says Carson. She recommends looking for a dehumidifier that has been ENERGY STAR certified.

“Any portable plug-in dehumidifier you set on a dresser or shelf in a room won't draw too much electricity,” says Dixon. “When not in use, unplug them to save on electricity. Naturally, the larger the portable dehumidifier, the more energy it will consume.”

A more costly option is a whole-house dehumidifier installed as part of the HVAC system. Dixon says this could be a good investment in high humidity climates because this type of dehumidifier reduces the largest amount of moisture from the air throughout the home. If you have high humidity in just one or two areas of your home, such as the bathroom and laundry room, a portable dehumidifier may be the better option since it’s less costly.

“Dehumidifiers can be added to your home's HVAC system and will keep your home at a comfortable humidity level by utilizing the home's duct system to condition all the air in the home and not just particular rooms,” says Dixon. 

The size of the dehumidifier you need depends on the size of your home and the level of humidity in your rooms.

Heat Pump Options to Lower Humidity

While you may not love the idea of overusing an air conditioner, consistently running it is one of the most effective ways to reduce humidity in your home, says Carson.

"Not only does your AC cool down the air in your home, but it also helps remove excess moisture in the air," Carson says. "To get the most out of your dollar, run your AC on 'auto' instead of 'on.' This will reduce your energy output while dehumidifying and cooling your home."

A high-efficiency heat pump can be a better option than a traditional air conditioning system.

"All heat pumps remove moisture from the air and reduce humidity in the home, and they can be used as an alternative to traditional heating and cooling systems," says Carson. "While heat pumps can struggle to warm up homes in extremely low temperatures, they are very efficient at cooling and dehumidifying homes in the summer months. They can also save you up to $950 per year."

A lot of homeowners overlook the dehumidification benefits of their air conditioner or heat pump, says Dixon.

"Proper sizing is important,” says Dixon. “Just like a regular residential air conditioning system reduces or lowers the humidity level in the home, so does a heat pump system. A high-efficiency residential heat pump system may remove more humidity due to having a larger condenser coil.”

Use Your Water Heater to Lower Humidity 

A somewhat surprising way to reduce your humidity is by using your water heater - that is, if you own a hybrid heat pump water heater.

"Hybrid heat pump water heaters extract moisture from the surrounding air, making them excellent at dehumidifying the surrounding space," says Carson. "These water heaters are highly efficient and may even eliminate the need for dehumidifiers in your home altogether."

Dixon says that a hybrid heat pump water heater in a basement may reduce the humidity in that area of the house depending on how much moisture is in the air and how long the water heater runs.

Rely on Renewable Energy to Power Systems 

If you live in a hot, humid climate like Florida or Texas, chances are you also see a lot of sunlight. One way to offset the additional electrical demands of a heat pump, a dehumidifier, and a hybrid heat pump water heater is to take advantage of your location and install solar panels.

Ventilation, vacuuming, and using air purifiers can reduce your exposure to the health impacts of humidity. Layer in the most energy-efficient dehumidifiers and heat pumps you can afford, then power them with renewable energy to fight back in the most effective and affordable way against dangerous levels of humidity.