How to Reduce Indoor Humidity Levels

How to Reduce Indoor Humidity Levels

No two ways about it, too much humidity feels yucky. When checking the weather, you might see extreme humidity levels and decide to skip going outside. And who would blame you? As humidity levels rise, your skin feels stickier, sweat dries slower, and bad smells linger. Not to mention the effects humidity can have on your home and the furniture within it! But just because you know what humidity is doesn’t mean you know all the ways to lower humidity. In this blog, we’ll give a brief explainer on the basics of humidity, reveal the ideal humidity for your home, and teach you how to reduce indoor humidity.


What is Humidity?

Humidity (specifically relative humidity, which is the kind you see on your weather report) is a measurement of the amount of water vapor in the air. Humidity is measured by a device called a hygrometer. You often see relative humidity expressed as a percentage, which is expressing how much water vapor is in the air relative to the dew point, which is the point at which the air can hold no more water vapor. As temperature increases, the air can hold more water vapor. Which means that raising the temperature of air lowers the relative humidity, and lowering the temperature of air raises the relative humidity.

If that’s a little confusing, here’s an easy way to imagine relative humidity. Imagine you’re pouring a water bottle into a bowl. If the bowl is bigger, the water bottle will fill a smaller amount of the bowl. Obviously, a smaller bowl will be more full from the water bottle. In this analogy, the water bottle represents the amount of water vapor, and the bowl represents the temperature of the air. There’s a little more science behind humidity—like how different types of air pressure affect relative humidity—but when you’re reading a weather report, these basics should help you understand what a humidity percentage means.


How Much Humidity is Too Much?

The ideal humidity level in your home is from 30 to 50%. Remember, this is a measurement of relative humidity, which means the actual amount of water vapor will shift as the temperature shifts.  What’s magical about the 30 to 50% range? 

Too much humidity is more than just uncomfortable. But it’s still uncomfortable! As the relative humidity increases, your sweat evaporates more slowly, which makes you feel warmer (and not to mention sweatier!). Humidity can damage water-absorbent paints. Ever noticed that bathroom paint tends to peel more than the pain in the living room? That’s because of the humidity from the shower expanding and cracking the paint on your bathroom walls. Wood furniture can also take a beating from humidity, expanding as the porous wood absorbs water out of the air. Finally—but perhaps worst of all—humidity encourages mold growth, which can lead to harmful respiratory conditions.

However, a home with no humidity is also problematic. When the humidity level gets too low, your skin dries out and your eyes can get irritated. In addition, certain respiratory conditions like asthma are exacerbated by low humidity levels. The ideal humidity level is somewhere in that 30 to 50% range. In the ideal range, you can breathe easily but aren’t wrecking your paint job or encouraging mold to grow.


Ways to Lower Indoor Humidity


When it comes to home climate control, there’s no magical fix. Instead, figure out which of these methods to reduce indoor humidity work best for you. Keep in mind that too little humidity can also be bad, and find the balance to optimize your home environment.


Use Your Air Conditioner

Every air conditioner dehumidifies the air as part of the cooling process. That’s because your AC condenses and evaporates warm air in order to create cool air. The warm air is ejected through the window via the AC unit’s exhaust, which conveniently shunts humidity out of your home as well.

Keep in mind that lowering the temperature in your home will lower the relative humidity. However, operating an air conditioner tends to lower the absolute humidity such that the relative humidity doesn’t increase too much.


Use Exhaust Vents 

Remember what we said about paint peeling in the bathroom? When trying to figure out how to reduce indoor humidity, give the bathroom fan a try. Your showers produce a ton of water vapor—that’s what ends up condensing and fogging up the mirror—and with that vapor comes more humidity. When taking a shower, make sure to turn the bathroom vent on. Sure, it’s noisy, but it will keep paint on your walls and the humidity level down.

Likewise, the kitchen fan can help mitigate the humidity increase from boiling water. Running your oven won’t raise humidity levels, but making pasta on the stove releases a ton of vapor into your home environment. Use your kitchen fan wisely and your home stay temperate even with a pot on the stove.


Consolidate Your Houseplants

Here at Windmill, we love the environment. We’re a green company, so we don’t want to tell you to keep greenery out of your home. But many plants produce humidity as part of their respiratory process. Having a ton of plants spread around might make your home seem livelier, but it will also raise the humidity level.

The humidity produced from plants is why greenhouses are so humid. If you’re having issues reducing your indoor humidity, try making a greenhouse room by consolidating your plants into a single area. Make sure the plants are in a well-ventilated environment so the humidity doesn’t get too intense. There are some plants, like succulents, which produce much less humidity than others. If you want to keep greenery spread around your home, consider a less-humid type of house plant.


Set Up a Dehumidifier

As the name implies, dehumidifiers are appliances expressly designed to lower the relative humidity in a home. Some central air systems actually have dehumidifiers built-in, so that your HVAC system more quickly creates a more temperate atmosphere. Standalone dehumidifiers might also decrease your AC usage, as an environment with less humidity will feel cooler. Most dehumidifiers have built-in hygrometers so you can tell when your home reaches the ideal 30-50% relative humidity.

If you don’t want to purchase a factory-made dehumidifier, there are a few ways to build one yourself. Charcoal (also known as activated carbon) is one of the best natural dehumidifiers. Set up a vase, bowl, or tin of charcoal and watch as the humidity is sucked out of the air. Make sure to replace the charcoal every few months so that it doesn’t become inundated with moisture.


Circulate the Air

Earlier, we mentioned that changing the air pressure will affect the relative humidity in your home. When figuring out how to reduce indoor humidity, try expanding the air in which air circulates. Allowing for more airflow usually decreases the air pressure, which will function to decrease the relative humidity. Running a ceiling fan or box fan won’t change the relative humidity level, but sitting in the path of a fan will remove the sweat from you, mimicking sweat evaporation and keeping you feeling cooler.

Even if it’s warm outside, you can use a hygrometer to check if the outdoor air is more humid than indoor air. If outside is less humid, open up the windows and let air circulate through. Just make sure you measure the outdoor air—you don’t want to bring more humidity into your home!


Humidity and You

As we said previously, there’s a lot of different ways to reduce indoor humidity. When figuring out the optimal ways to lower humidity in your home, make sure to try a few different methods. Remember also that, as the seasons change, humidity will behave differently. In cold winter air, a small amount of humidity goes a long way. Likewise, in the summer, you may need less specific dehumidifying measures since your AC is running. But also remember that dehumidifying your home will keep you feeling cool, so your AC may be less necessary.

For more info on humidifiers and how they work with your AC, check out our blog on the subject. For specific info on cooling down an upstairs apartment, we’ve also written a blog on that. If you have questions about staying comfortable with your AC, our support team is available every day of the week to help you out.