What Is the Ideal Indoor Humidity Level in Winter at Home?

A view of a winter's day through a window

Most of us tend to focus on the indoor temperature during winter, but we forget to consider indoor humidity. Humidity plays a vital role in keeping your indoor environment healthy and comfortable. So, it’s essential to maintain an appropriate humidity level in your home year-round.

Low humidity can cause dry and itchy skin, nosebleeds, cracked lips, and a miserable night’s sleep. In contrast, high humidity in your home can promote mold growth, which can lead to various problems, including health issues and structural damage.

What is Relative Humidity?

You can measure humidity in several different ways. However, relative humidity (RH) is the most common. Relative humidity is expressed as a percentage. It is a ratio of the current amount of water vapor (moisture) in the air and the maximum amount of vapor the air can potentially contain at a given temperature. A 100 percent relative humidity reading means the air is saturated as it is holding as much moisture as it can at a given temperature.

Colder air holds less moisture than warmer air. So, humidity increases in summer when the temperature is warmer. While in winter, when the temperature drops, the humidity naturally drops. Using your heating system in winter can also exacerbate the problem of low humidity and dry out your indoor air. When you heat your home, the water vapor capacity of the indoor air increases while the moisture content in the air doesn’t change. As a result, the relative humidity can drop uncomfortably low during the wintertime.

Read on to find out how you can maintain the ideal indoor humidity level in winter while enjoying a comfortable temperature.

The Most Comfortable Indoor Humidity Level in Winter

Person relaxing in a cozy room

Maintaining the ideal indoor humidity in winter is a balancing act. Too much moisture can result in condensation and mold growth, while too little will result in discomfort and potential health concerns.

So, what is the ideal indoor humidity level in winter? According to the EPA, indoor relative humidity should be kept below 60% and ideally between 30% and 50%, this is also the ideal humidity level for a baby’s room. This humidity range will ensure your home is not too dry and not too humid during winter. It’s the ideal range for your health, comfort, and your home’s structural integrity.

How to Monitor Humidity in Your House

A hygrometer inside a home

To measure the relative humidity inside your home, you will need a hygrometer. Most digital hygrometer models are inexpensive and easy to use. Some hygrometers have multiple sensors, letting you keep tabs on humidity throughout different areas of your home. The top models have remote monitoring capabilities through WiFi or Bluetooth, so you can use your smartphone to monitor remotely the conditions of your home from anywhere. To find the right hygrometer for your needs, take a look at our extensive review of the top models here.

A digital hygrometer makes it simple to monitor conditions and helps you maintain an appropriate amount of moisture in your home. A hygrometer will also measure the ambient temperature for you, which will help you reach the recommended indoor temperature during winter.

The Problems Low Humidity Can Cause

Low humidity in winter can result in dry conditions that can affect your comfort and health, and it can also cause damage to your home. Here are some of the most common issues associated with low indoor humidity:

  • Dehydrated skin: Your skin has a moisture barrier that needs constant replenishment. This moisture barrier evaporates faster in a dry environment, making your skin itchy, flaky, and cracked. While moisturizers can help, maintaining ideal humidity levels in winter is a more sustainable solution. Naturally, we sweat more when we sleep, so setting where to put the humidifier is also essential for a great result.
  • Scratchy throat: A scratchy throat is often a warning sign that you’re about to get sick, but it can also be a symptom of a dry environment. Your throat contains mucous membranes that dry out quickly, leading to the feeling of a dry, unpleasantly scratchy throat.
  • Irritated sinuses and nosebleeds: Just as with a scratchy throat, your sinus cavities and mucous membranes in your nose can dry out quickly, leading to a burning or irritating sensation. Nosebleeds can result from dried, irritated mucous membranes, and the easiest solution is to increase the humidity. For more help with this issue, see our article here to find the best humidifier for nosebleeds.
  • Static electricity: When your home is appropriately humidified, the static electricity in the air naturally dissipates. However, indoor air is excellent at storing electrons when it is dry. This build-up of static electricity can cause unexpected electric shocks when you touch a conductor, such as a doorknob or a metal surface.
  • Wood damage: Overly dry air will absorb the moisture out of the wood in your home, leading to the wood cracking, splitting, and bending. In particular, dry air can damage wooden floors, the wooden frame of your home, furniture, and even musical instruments. While properly treated wood is more resistant to dry air, long-term exposure raises the risk of damage.

How to Increase Indoor Humidity in Winter

Women relaxing with humidifier running

A humidifier is the most reliable and effective way to increase indoor humidity in winter. A humidifier can rapidly add moisture to the air and maintain a comfortable humidity level with its built-in humidistat.

Humidifiers can range dramatically in size and function. Portable evaporative or ultrasonic humidifiers can increase humidity in a single room, while whole-house humidifiers attach to your HVAC system and control humidity throughout the whole home. No matter which option you choose, make sure to buy a suitable model for your home’s size and your needs. For help selecting the best model for your home, read our large humidifier guide.

Other ways to humidify your home in winter include:

  • Air-drying your clothes inside: Instead of using a tumble-dryer, let your clothes dry inside in a room or living area that you want to humidify. The moisture will evaporate from the clothes into the air and raise your indoor humidity levels as they dry.
  • Adding houseplants to your home: Plants release moisture into the air through a process called transpiration. The more plants you have, the more noticeable the moisture-releasing effect—as long as you remember to water them!
  • Showering with the door open: Your bathroom is often the most humid room in the home. You can spread this humidity from a hot shower to other places by showering or bathing with the door open. Be sure to warn other household members in advance!

What Are the Dangers of High Humidity Levels?

While uncommon in winter, there is still a possibility of having too much humidity in your home. Condensation is often the first sign that you are over humidifying your home. Condensation occurs when moisture-laden warm air hits a cold surface or when there’s too much humidity in your home. The water vapor condenses and forms water droplets. If left untreated, the condensation can lead to mold growth and wood rot.

You can fix high humidity through various means, including:

  • Turning down humidifier settings.
  • Improving ventilation and ensuring exhaust fans in your bathroom and kitchen are working correctly.
  • Using a dehumidifier.

Final Thoughts

Humidity can have as much of an impact on your comfort as the temperature does. Especially when you're trying to obtain the best humidity level for sleeping. Maintaining the ideal indoor humidity level of 30%-50% in winter can be tricky when heating your home. However, if you use the right-sized humidifier for your home, you can avoid the consequences of dry indoor air while staying cozy and warm throughout the season.

Published: February 7, 2022

Leave a Reply