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Relative Humidity

You can create a dry, mold-free, and comfortable indoor environment by controlling the level of humidity in your home.

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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 delve into relative humidity so you can learn how to measure it, how it affects your home, and steps you can take to keep it at an optimum level. 

Relative humidity

What Is Relative Humidity? 

Relative Humidity (RH) is a term used to describe the volume of moisture that the air can hold at a certain temperature. It’s usually expressed as a percentage. If the relative humidity is 50%, that means the air has a fairly high amount of moisture. If the figure rises to 100%, we say the air is saturated with water vapor. In such instances, the air isn’t able to hold any more water vapor. 

Your home’s relative humidity isn’t constant. It changes with the outside temperature. When the temperature rises, the air holds more water. But, when it drops, the air’s ability to hold water goes down as well. Problems will start appearing when relative humidity rises to 70%. That’s an easy threshold to surpass if there are unresolved moisture issues. 

Moisture Sources in the Home 

Water or moisture can get into your home in many ways. It can be through roof leaks, houseplants, clothing dryers, rainwater, or leaking water pipes in your kitchen or bathroom. The latter sections have a propensity to get wet or damp for obvious reasons. 

What Is the Optimal Relative Humidity? 

The Environmental Protection Agency (EPA) encourages homeowners to aim for 30% to 50% relative humidity. Keeping humidity in that range ensures the indoors remain comfortable and bearable. Surpass this range or go lower, and you will find yourself contending with a myriad of issues. 

High Relative Humidity in Your Home 

Excess moisture isn’t good for your home as it can encourage the growth and spread of mold spores, fungi, and harmful bacteria. Mold will grow and attach itself to your wooden supports, drywall, and insulation. 

These microorganisms can trigger health issues and reduce the quality of the indoor air. Anyone with asthma will experience a flare-up. In addition to instigating respiratory problems, high relative humidity does encourage wood rot. Your wooden joists and support beams will start rotting, leaving you with weak supports, damp artwork, soggy furniture, and bouncy floors. 

Wallpapers will start peeling and paint bubbling. Moisture droplets will also form on your windows and walls when the air gives up its moisture. In addition, wooden door and window frames may decay and lose their natural strength. Over time, your electronic appliances or equipment may malfunction. 

To beat back moisture, you will have to run your air conditioner for many hours. This translates into higher monthly utility costs.  

Low Relative Humidity 

A drop in humidity levels can also affect your home adversely. As well as causing wood floors to warp or separate, the dry air might also cause gaps around the ceiling and walls. You will also notice that wooden windows and frames will shrink, and this can affect their function. 

Attaining Optimal Relative Humidity 

It’s not that difficult to control relative humidity in your home and keep it at an optimal level. For a start, you can install a dehumidifier in your basement or crawl space to dry out the damp air. Your local basement contractor can help with sizing and installation. Go for a unit with a self-draining mechanism and an air purifier. Each morning, you won’t have to empty the bucket of water like you would with typical home dehumidifiers. Plus, it will clean the air so you can breathe easily. 

Flooding remains a threat to your home. Whether it’s due to rainwater or a leaky tap, it can inundate the basement or crawl space and raise the humidity levels. You can prevent flooding by installing an interior drainage system and a sump pump. Anytime water enters the basement or crawl space, the perimeter interior drainage system will intercept it and direct it to the sump pump that will quickly remove it from your home. 

Lastly, if you have a crawl space, seal any open vents and encapsulate it with a heavy-duty plastic vapor barrier. It will lock out moisture-laden air and prevent air exchange. Your crawl space is going to stay dry all year round. 

When the relative humidity goes up, you will experience undesirable effects such as mold and mildew growth, musty odors, and warped wooden floors. Don’t let it drive you insane. Schedule a free inspection and repair quote with Complete Basement Systems and get a lasting fix to your problem. 

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