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Relative Humidity

Having the level of right humidity in your home matters. Here is an in-depth guide on relative humidity and the effects it can have on your home.

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You probably learned a thing or two about relative humidity in school but didn’t quite understand how it affects your life. Fast forward a decade or two, and you now realize it’s not just a concept. It is a phenomenon that affects your home. 

True, relative humidity can have adverse effects on the comfort of your home. High humidity is known to encourage mold growth, attract pests, and trap dirt plus allergens that are harmful. But that’s not all. Low humidity can also cause health issues, especially nose, eye, and throat irritation. Worse still, runaway humidity can set the stage for structural problems around the house. 

What Is Relative Humidity? 

Relative humidity is a measure of the total amount of moisture the air can hold at certain temperatures. Temperature, air saturation, and the dew point are some of the variables that affect relative humidity. Because of the variables involved, relative humidity in a space is always changing. 

Generally, relative humidity is expressed as a percentage. And the higher the relative humidity percentage, the more humid your air is. When the relative humidity is at 100%, it means the air is saturated and is at its dew point. 

What Is the Ideal Level of Indoor Humidity? 

The Environmental Protection Agency (EPA) recommends keeping humidity above 30% to avoid condensation on your windows in winter and below 50% in summer. Ideally, your indoor relative humidity should range between 30 to 60 percent at all times for comfort and the prevention of microorganism growth. Anything lower or higher than the recommended humidity is a recipe for health and structural problems around the home. 

How to Measure It 

Take the current pressure point in the air and divide it by the pressure point at which water vapor saturates the air. You can also measure relative humidity using a psychrometer. This device comes with two thermometers. One thermometer measures wet-bulb temperatures while the other measures dry-bulb temperature. 

Why Relative Humidity Is Important 

Indoor humidity that is either too high or too low can cause a myriad of problems that touch on your health and home’s comfort. 

Effects of High Humidity Levels 

Lowers indoor air quality: High moisture levels in the home create a favorable environment for the growth and spread of fungi, bacteria, mold, mildew, and viruses. These pollutants contaminate indoor air quality, causing illness. 

Aggravates health issues: When indoor humidity levels go up, anyone with asthma or allergies may experience a flare-up of symptoms. 

Damages your structure: Extreme moisture also fosters the growth of fungi which contributes to wood rot. Decaying wood is extremely damaging to your home as it causes bouncy floors, musty odor, and termite infestations. This moisture also causes damage to wood floors, artwork, furniture, and even electronics. 

Drives up your energy bills: Your damp and muggy home will make the interior hot and uncomfortable, and this will force you to turn up your air conditioner. This will lead to more energy consumption. 

Effects of Low Humidity Levels on Your Home 

Low relative humidity indoors can also cause a host of issues for you and your home. For instance, when the air in your home is too dry, it can irritate the mucous membranes causing your asthma and allergy symptom to worsen. Cold and flu viruses spread more quickly, putting you at risk of developing sinus infections. You may also suffer from chapped lips, and dry skin and air passageways. 

Dry air can also be damaging to your home. Moisture scarcity affects wood and construction materials negatively. Your walls and ceiling may start to crack, wood floors may separate and your door and window frames may start shrinking. 

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 JES Foundation Repair to schedule a free crawl space inspection and estimate

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