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Relative Humidity

The amount of water vapor in the air measured as a percentage. The percentage expresses the amount needed for saturation at the same temperature.

Understanding Relative Humidity

Like it or not, relative humidity greatly impacts comfort levels in your home. Ignore it and you will have to deal with all the unpleasant effects of moisture.  

Let’s explore the details about below-grade humidity. But first, we’ll explain what humidity is before we get into the meat of this topic: damage and prevention. 

What Is Relative Humidity?  

Relative humidity will tell you how much moisture is currently in the air compared to what the air can hold at that temperature. Some of the factors that can affect relative humidity are air saturation, temperature, and the dew point. Due to these changing factors, relative humidity is always changing as well.   

Relative humidity is expressed in percentages. The higher the percent, the more humid your air is. 

What Is the Ideal Level of Indoor Humidity?  

According to the Environmental Protection Agency (EPA), the ideal range of relative humidity for a home is between 30% and 50%. Anything higher or lower than that is likely to cause problems. This, of course, depends on the climate you live in as well as your personal preference.   

How Will High Humidity Affect My Home?  

As we’ve said, both high and low humidity are dangerous for several reasons. So, let’s take a look at what high humidity does to both you and your home.  

Air Quality:

Fungi, bacteria, mold, mildew, and viruses all love high humidity. As such, they’ll run rampant in your home if you don’t keep it at a desirable level. But if you allow humidity to go so high, you’ll experience poor air quality. This will only lead to health problems which you don’t want to face.  

Health Issues:

In case you or some of your family members have asthma or allergies, high humidity will only worsen them. It will flare up the symptoms, making them almost unbearable to live through.  

Structural Damage:

Fungi don’t only affect the air quality. They will endanger the structural integrity of your home as well by causing wood rot. And since most homes use lumber for various purposes, you can count on bouncy floors, musty odor, and termite infestation. But that’s not all. Fungi will damage your furniture and even electronics.  

Costly Energy Bills:

High humidity levels will cause your home to be muggy with uncomfortable hot air. This will force you to use your AC system even more, leading to higher energy consumption and bills. 

How to Control Relative Humidity in Your Home  

Managing indoor humidity should be a priority for every homeowner. Some effective ways to maintain acceptable moisture levels in your home include;  

Crawl Space Encapsulation  

If you have a dirt crawl space, moisture can seep into your home through the ground, increasing your relative humidity. To avoid this problem, you need to invest in professional crawl space encapsulation. This entails covering the dirt floor and walls with a 20-mil vapor barrier. What this does is lock out outside air and prevent moisture from seeping through the dirt floor.  

Seal Crawl Space Vents  

Warmer air holds more water than cooler air. As such, it is common for outdoor air to be more humid during the summer months. This is also true for homes in the coastal regions because the surrounding air absorbs the water from the ocean.  

That said, open vents allow warmer outdoor air to circulate your crawl space. This warm air damps its moisture in your home through condensation, leaving you with a humid crawl space. To prevent this, tightly seal off your crawl space vents and door to prevent outdoor humidity from entering your crawl space.  

Install Dehumidifiers  

Dehumidifying your crawl space or basement is another good way of controlling your relative humidity levels. A dehumidifier clears excess moisture from the air in your home, making the indoors less muggy and less attractive to mold and other thirsty insects and pests.  

If the air in your home feels musty and uncomfortable, contact the Groundworks experts in your area to schedule a free crawl space inspection and estimate. 

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