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What Is Relative Humidity?: Its Impact on Your Crawl Space

crawl space humidity reader showing 20% relative humidity

Humidity can cause numerous problems. From health issues to structural damage, both low and high levels of it will seriously affect your home. For example, low humidity can encourage nose, eye, and throat irritation. On the other hand, high levels of it can boost mold growth, pest presence, and even dangerous allergens in the lower-grade levels of your home. 

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

What Is Relative Humidity?

Firstly, let’s look into what relative humidity is. Relative humidity refers to the total amount of moisture in the air at a certain temperature. It depends on a couple of variables such as air saturation, the dew point, and the heat level. Depending on these variables, humidity will constantly be changing and affecting its surroundings in different ways. 

We express it as a percentage, meaning that the bigger the number, the more humid the air is. In scenarios when the relative humidity is at 100%, the air will experience saturation that will bring it to its dew point. Of course, these are extreme situations that you’re unlikely to experience. 

The Ideal Level of Humidity Indoors? 

Relative humidity will vary depending on the time of the year. In winter, it will go down, while in the summer, it will jump up. You can easily notice that there’s something wrong when there’s condensation on your windows. 

The Environmental Protection Agency (EPA) suggests that you should keep the level of humidity above 30% during cold days and under 50% when it’s hot outside. In an ideal scenario, the relative humidity indoors would be between 30 and 60 percent. This level will provide you with comfort and will also prevent the growth and spread of dangerous microorganisms throughout your home. 

If you keep relative humidity outside that safety range, you can pretty much count on experiencing health issues and structural damage. So, it’s safe to say that measuring it properly will save you from costly medical and home repair bills. 

How to Measure Relative Humidity

crawl space humidity reader showing 16% relative humidity

This might get a bit tricky but bear with us. Namely, you’ll first need to measure the current air pressure in your home. Once you do that, you’ll need to divide it with the pressure point at which water vapor saturates the air. 

If this seems like too much, you can use a psychrometer to determine the indoor relative humidity. The psychrometer comes with two separate thermometers. The first one will measure the wet-bulb and the other will determine the dry-bulb temperature. 

Either way, we suggest that you contact a professional. If you suspect that the humidity levels around your home are too high or low, it’s best to have someone with experience helping you. As relative humidity can cause numerous problems, you’ll want someone to measure it properly. 

How High Humidity Affects Your Home

humidity problems
  • 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 in Michigan use timber 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. 

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. 

Low Humidity Levels 

Just like high humidity, low levels will cause you and your family health issues. The dry air will allow cold and flu viruses to spread more quickly. Also, it will affect asthmatics, irritate your nose, eyes, and ears, as well as your skin. It’s just as bad as the other extreme. 

Yet, that’s not all. Low humidity levels will cause structural damage in your home. It will damage both wood and other construction materials. Your walls and ceilings might begin to crack while the wooden floors will separate. Moreover, the doors and windows won’t be able to open or close properly as their frames will start to shrink. 

Controlling Relative Humidity 

Luckily, there are ways to control the level of humidity in your home. Some of them include crawl space encapsulation, sealing vents, and dehumidifiers. Let’s take a look at them. 

1. Crawl Space Encapsulation 

Professional crawl space encapsulation includes covering the dirt floor beneath your home as well as its walls with a thick vapor barrier. This way, you’ll be able to lock out outside air and prevent moisture from coming inside. Of course, this isn’t something you can do yourself. You’ll need professional help to make sure you encapsulate your crawl space properly. 

2. Sealing Crawl Space Vents 

Since warm air holds more water, you will experience high humidity levels during summer if your crawl space vents are open. Warm air will create moisture through condensation and leave you with a humid home. Hence, it’s important to seal your vents tightly with professional help. 

3. Dehumidifiers 

By installing a dehumidifier in your crawl space, you’ll be able to keep the relative humidity at a desirable level. It will clear excess moisture from the air in your home, making it less attractive for mold, insects, and pests. 

In case you’re looking to solve high or low humidity levels in your home, you can contact our team at FSM to schedule a free crawl space inspection and repair estimate now. Our professionals can further help you install one of the previous solutions in no time.

Relative Humidity FAQs

The price varies based on the size and condition of your crawl space, as well as necessary repairs. Foundation Systems of Michigan offers free inspections, no-obligation quotes, and flexible financing to accommodate your budget.

An exhaustive crawl space encapsulation, which includes waterproofing, insulation, and dehumidification, blocks external water and air from penetrating and elevates humidity within. The result is reduced humidity levels when these external elements are prevented from introducing moisture. Reach out to Foundation Systems of Michigan to find out more and to schedule a no-cost inspection.

The duration required to correct crawl space humidity varies with the extent of the issue, but our goal is to offer prompt and thorough solutions. Foundation Systems of Michigan’s crawl space encapsulation procedure is usually completed within a day, perhaps two for larger spaces. Contact us to book a free inspection, receive a no-obligation quote, and obtain a detailed time estimate.

Michael Wilcher

Michael Wilcher

Michael Wilcher is the Content Lead at Groundworks, helping us to answer all of our customers biggest questions about foundation repair, basement waterproofing, crawl space encapsulation, and concrete lifting. In his free time, Michael enjoys collecting vinyl records, watching Formula 1 Racing, and reading philosophy. He holds an MPhil from the University of Cambridge.

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