What's the Best Humidity Level for Sleeping?

We often focus on room temperature when trying to create the perfect sleep environment for falling asleep quickly and easily. We first think of turning the fan on, adjusting the AC, or piling on the blankets.

But there's another, often overlooked, factor that plays a huge role in how well you sleep: humidity. The amount of moisture in your bedroom air can affect everything from how easily you fall asleep to how often you wake up at night. Too much humidity, and your room will feel heavy and sticky. Too little humidity, and you'll wake up with dry skin and a sore throat.

Therefore, if you want to discover the best humidity level for sleeping, read on! In this article, we'll explain how humidity affects sleep, what the ideal humidity range is, and how to maintain it.

Key Takeaways

• Humidity affects your body's ability to regulate temperature. High humidity makes it harder for sweat to evaporate, interfering with the body’s natural cooling process during sleep. This can lead to overheating, restlessness, and poor sleep quality.
• The ideal indoor humidity range is 30–50%. Staying within this range helps reduce allergens like mold and dust mites, while preventing dry skin, nasal irritation, and breathing discomfort that can disturb your sleep.
• Temperature and humidity must be balanced. For optimal sleep, both humidity and temperature should be kept within healthy ranges, typically around 65°F (18°C) and 30–50% humidity.

Does Humidity Affect Sleep Quality?

Humidity can definitely impact sleep quality. For example, high humidity can:

• Increase wakefulness, according to the Sleep Foundation. It can also reduce the amount of time spent in NREM (slow-wave sleep, which is crucial for tissue repair and muscle recovery) and REM sleep (rapid eye movement sleep, during which dreaming occurs). Both sleep stages are extremely important for our overall health.
• Cause mold growth, which, over time, can affect your overall well-being. Mold can cause allergies and other health issues.
• Provide a thriving environment for dust mites.
• Causes excessive sweating, which can disrupt sleep.
• Worsen sleep conditions like sleep apnea or insomnia by disrupting breathing and thermal comfort.

Conversely, research suggests that low humidity can:

• Cause dry skin, a sore throat, and itchy eyes.
• Exacerbate respiratory issues.
• Increase the likelihood of nosebleeds.
• Exacerbate issues like eczema or allergies.
• Increase the likelihood of respiratory infections.

In conclusion, both extremes of humidity can have significant health implications. So, whether it’s high or low humidity, maintaining appropriate humidity levels is crucial for ensuring a restful night’s sleep. But what exactly is the best humidity level for sleeping? Let's find out!

What Is the Best Humidity Level for Sleeping?

The best humidity level for sleeping is between 30% and 50%, according to the Environmental Protection Agency. However, some studies show that the best humidity for sleeping is between 40% and 60%. This is the best relative humidity for sleep because it helps prevent mold and dust mites (which thrive above 60%), while also keeping your skin and respiratory system from drying out (which often happens below 30%).

For example, if you have issues like dry skin or respiratory issues, you'll likely find it easier to sleep in a room with humidity above 40%, as lower humidity can worsen health problems - asthma symptoms, for instance. Regardless, make sure to keep the humidity below 60% to avoid mold growth and other problems.

Keep in mind that humidity may shift with the seasons. In winter, indoor air may be dry in some regions, in which case you may need to use a humidifier. In summer, especially during humid nights, you'll likely need to use a dehumidifier.

Relative Humidity vs Absolute Humidity

While most guidelines talk about humidity in percentages, those percentages refer to relative humidity: how much moisture is in the air compared to how much it can hold at a given temperature.

But there’s also something called absolute humidity, which measures the actual amount of water vapor in the air regardless of temperature. This is important because the same relative humidity can feel very different in summer versus winter.

Nonetheless, thermostats measure relative humidity, not absolute humidity, because it tells you how humid the air feels to your body at a given temperature. For example, 50% relative humidity at 77°F (25°C) feels much more humid than 50% relative humidity at 59°F (15°C), even though the absolute humidity is lower in the cooler room.

That’s why temperature and humidity should always be considered together. They directly influence each other and how the air feels on your skin and in your lungs.

Ideal Temperature Range for Sleeping

It is generally recommended to keep the thermostat at 65°F (18.3°C). This is the best temperature for sleeping, even though it seems that it would be a bit chilly. In reality, body temperature slightly drops as we get ready for sleep, according to Okeanis Vaou, a UT Health San Antonio neurologist specializing in sleep medicine.

However, this temperature may be too low for some. In this case, you can apply the following rule: keep the room temperature a few degrees cooler than the daytime/evening room temperature. For example, if you generally keep the room temperature at 74°F (23.3°C), lower it to 69°F (20.5°C)  at night.

Ultimately, it's equally important to maintain the room temperature within the recommended range. For example, even if you do lower humidity levels, you'll still feel too warm to sleep if the room temperature is too high. Conversely, if the room temperature is within recommended ranges, but the humidity is high, you'll still feel sweaty and uncomfortable.

Signs Your Bedroom Humidity is Not Ideal

If you don't have a hygrometer yet, you'll have to look for signs of high/low humidity yourself. However, keep in mind that if you want to maintain humidity levels within the recommended range, it's best to get a hygrometer that will constantly monitor relative humidity.

Signs of High Humidity

Indicators that your room’s humidity is too high include:

• Visible mold growth
• A musty odor in your bedroom
• Difficulty breathing
• The feeling of heavy, humid air
• Sweating excessively
• Damp sheets
• Warped wooden furniture

Signs of Low Humidity

Signs of low humidity include:

• A dry throat
• A dry nose
• Uncomfortable sleeping
• Frequent nosebleeds
• Damage to wooden furniture (it can dry out and crack over time)

Tools to Measure Indoor Humidity

The best tool for monitoring humidity levels is the digital hygrometer. It can provide real-time humidity readings for any indoor space, helping you monitor and adjust humidity levels as needed. Some smart humidity monitors even connect to Wi-Fi. This feature allows you to check the indoor humidity levels via a smartphone app.

Alternatively, you can use portable humidity monitors for specific areas like greenhouses or wine cellars.

For more comprehensive humidity control, you can install a humidistat. It can help maintain desired humidity levels by connecting to your HVAC system.

Tips for Maintaining Optimal Humidity Levels

Here are some tips for maintaining humidity levels within the optimal range:

• Use a programmable thermostat. It can adjust indoor conditions based on your daily routine. This device allows you to set specific temperature and humidity ranges for different times of the day. This way, you can ensure that your bedroom environment remains comfortable and conductive for sleep.
• Change your bedding and mattress. Avoid synthetic bedding. Instead, use breathable materials, such as cotton or linen. Also, it's recommended to replace memory foam mattresses, as they are not ideal for humid environments.
• Enhance air circulation. This can improve air quality and mitigate humidity issues. You can use fans or adjust your air conditioner.
• Use a dehumidifier if the humidity is too high.
• Slightly open windows at night to allow air to circulate. Breathing can cause too much humidity, and keeping the window open can help remove some of that humid air.
• Buy some houseplants if the humidity is too low. Houseplants are known to increase humidity levels.

The Role of Your HVAC System in Maintaining Humidity Levels

Heating, Ventilation, and Air Conditioning (HVAC) systems do more than just regulate temperature. They play a crucial role in controlling indoor humidity as well. Here’s how they work to maintain healthy and comfortable humidity levels:

1. Dehumidification (Removing Moisture)

• Air conditioning: when your air conditioner runs, it cools the air by passing it over cold evaporator coils. As warm, humid air touches these coils, moisture in the air condenses into water droplets and is drained away. This process reduces indoor humidity, making the air feel cooler and less sticky.
• Dehumidifiers: some HVAC systems include dedicated dehumidifiers. These are especially helpful in areas with persistent high humidity. These units work alongside the main system to remove moisture from the air even when cooling isn’t needed.

2. Humidification (Adding Moisture)

• Humidifiers: in winter or in dry climates, heating systems can make indoor air too dry. Many HVAC setups include humidifiers that maintain higher moisture levels, preventing issues like dry skin, irritated eyes, and static electricity. This is especially important for protecting wood furniture and floors from cracking because of low humidity.

3. Ventilation and Air Exchange

• Ventilation systems: proper ventilation helps control humidity by exchanging stale, moist indoor air with fresh outdoor air. Advanced systems like Energy Recovery Ventilators (ERVs) and Heat Recovery Ventilators (HRVs) can manage this exchange efficiently, maintaining balanced humidity while conserving energy.

4. Smart Controls

• Sensors and smart thermostats: modern HVAC systems often include humidity sensors (hygrometers) and smart thermostats. These devices monitor indoor humidity and adjust system settings automatically to keep levels within the ideal range (typically 30–50% relative humidity).

The Role of Windows and Doors in Maintaining Humidity Levels

Your HVAC system isn't the only one that helps maintain humidity levels within recommended ranges. Your windows and doors are just as important. More precisely, they influence how moisture moves and is managed indoors, particularly in bedrooms, where we spend long, uninterrupted hours at night. Here's why:

• Superior sealing: advanced windows and doors feature tight seals and weather stripping. These prevent unwanted moisture from entering the house during humid seasons. They also keep indoor air from escaping when it’s dry outside. This helps keep humidity levels stable throughout the night.
• Thermal insulation: energy-efficient windows and doors with double or triple glazing and insulated frames reduce temperature swings. They keep indoor surfaces warmer in winter and cooler in summer. Because of this, there's a lower risk of condensation and thus mold growth.
• Proper ventilation: bedroom windows need to open fully to allow plenty of fresh air in. For example, it's not recommended (and actually prohibited by egress building code requirements) to install awning windows in the bedrooms, as they don't open fully like casement windows and cannot properly ventilate the room.

How Windows and Glass Doors Affect Indoor Humidity

Ultimately, your HVAC system may be of the highest quality, but if your windows and glass doors aren't properly insulated, you'll still struggle to maintain desired humidity and temperature levels. Therefore, if your windows or glass doors don't close properly, are old, or are poorly sealed, it may be time to replace them.

In this regard, Magic windows and glass doors stand out in the industry thanks to their advanced engineering and thoughtful design. More precisely, they are built with high-performance seals and multi-layered insulations. This means they have no gaps or cracks that can allow humid or dry air to sneak in.

Our windows and glass doors are also at a much lower risk of developing condensation, which is of the essence in cold climates. Furthermore, when you do want to ventilate your bedroom before or during sleep, you can easily do so: our windows and glass doors feature an innovative opening mechanism that allows for easy, controlled airflow. Not to mention that they come with our fully retractable screens, which means you can keep your windows open at night without the fear of letting bugs in!

All in all, Magic windows and glass doors combine cutting-edge insulation technologies, airtight seals, and user-friendly features to deliver unmatched control over indoor humidity and temperature.

Curious to learn more about them? Eager to discover how Magic products can help you achieve the ideal bedroom humidity? Give us a call AT 1866-OK-MAGIC!

Final Thoughts

We tend to think of comfort as a single number on a thermostat, but true sleep comfort is more like a recipe, and humidity is a key ingredient. Just like you wouldn't bake bread with only heat and no moisture, your body can’t fully relax in a room that’s cool but clammy, or dry as a desert.

Paying attention to humidity isn’t just about luxury; it’s about giving your body the indoor environment it needs to rest, repair, and reset. So if you’ve already optimized your mattress, your sheets, and your bedtime routine, the next step might be invisible, but powerful: balance the air itself. Sweet dreams!

Frequently Asked Questions

Is it better to sleep in humid or dry?

It’s not recommended to sleep in humid or dry air. To get better quality sleep, it's important to maintain humidity levels between 30% and 50%, never exceeding 60%, to avoid dryness and excess moisture that disrupts comfort and causes breathing problems.

Will mold grow at 55% humidity?

Mold can start growing at 55% humidity, especially in poorly ventilated or warm rooms. It will thrive in environments with humidity levels above 60%.

What is the best humidity level for sleeping in winter?

In winter, aim for a humidity level between 30% and 50% to prevent dry/humid air issues like mold growth or irritated skin and sinuses.

Is it bad to sleep in 80% humidity?

Sleeping in 80% humidity is not recommended, because it can disrupt your sleep stages and increase the risk of allergens like mold and dust mites.

What are the signs that my bedroom humidity is too high?

If you notice damp sheets, a persistent musty odor, visible mold growth, or feel sweaty upon waking, these are clear signs that your bedroom humidity is too high.

How can I increase humidity in my bedroom during winter?

To effectively increase humidity in your bedroom during winter, consider using a humidifier, boiling water on the stovetop, or incorporating indoor plants.

Why is regular maintenance of HVAC systems important for humidity control?

Regular maintenance of HVAC systems is crucial for effective humidity control, as it ensures efficient operation, prevents mold growth, and helps avoid increased energy costs.