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Crawl Space Dehumidifiers Bring Better Air Quality to Your Home

Any home with a crawl space should consider a dehumidifier to maintain proper indoor air quality.

This is because moisture levels in a crawlspace are often high, and this excess moisture can work its way into your living space along with mold and mildew.

With a quality crawl space dehumidifier, as well as proper insulation and encapsulation, you’ll have better comfort and superior air quality in your home. This also applies to basements where humidity levels can run high.

crawl space entrance

Improved Air Quality and Lower Moisture to Your Home


Poor Air Quality Because of the Stack Effect

There is an important scientific principle that relates to the comfort, temperature, and air quality of a home: the stack effect.

No matter how well your home and crawl space is insulated, air will eventually move from top to bottom. This means that whatever airborne particles you have on the first floor will eventually work their way to the second floor. It also means that whatever particles you have in the crawl space will eventually work their way up to the first floor.

Air brings along basically everything it holds: moisture, mold spores, chemicals, leavings from dust mites, and dust are all carried with the air. Therefore, if your crawl space has high humidity, soon your living space will too.


How to Tell if Your Home Needs a Crawl Space Dehumidifier

Some homes won’t need a dehumidifier. (Homes without crawlspaces obviously won’t!)

However, if you have a crawl space under your home, there are some signs that you may need to install one of these appliances.

First, if your home smells musty, you may have high humidity levels stemming from the crawl space. Excess moisture creates the perfect area for mold growth, and you can often smell it before you ever see it.

Another sign is allergy and asthma outbreaks when you are home. Obviously allergic reactions and asthma attacks can be caused by a vast assortment if issues, but if you notice more problems while you are at home as opposed to school or work, it may be mold spores seeping up from the lower level.

If you have noticed damage to the structure of your home, especially towards the bottom near the ground, it’s likely caused by moisture that can be at least reduced by a crawl space dehumidifier. Damage can be caused by insects, wood rot, rust, or even sagging insulation, all of which could be caused by excessive moisture and therefore reduced by a dehumidifier.

Another strong indication that you need a dehumidifier is if you have any utilities under your home. If you have HVAC ducts or water pipes, or even appliances, you can protect them by ensuring the crawl space does not have high amounts of moisture.


What is a Crawl-Space Dehumidifier?

Some homes sit over a crawl space, which is an area that is vulnerable to high humidity, potentially leading to mold growth, pest infestations, and structural damage. It can even reduce the air quality in your home, creating issues for people with respiratory issues and exposing everyone to potentially harmful air pollution.

A crawlspace dehumidifier is exactly what it sounds like: a dehumidifier that is installed in your crawl space. You might think that any dehumidifier will do, but there are products that are designed and manufactured specifically for use in a crawl space. Not only are they powerful enough for high moisture levels often found in crawl spaces, they also have the appropriate mounting to be installed in the space.

These units do not sit on the floor, but instead have a mounting system that suspends them to the trusses that create the top of the space and the lower-level floor. They pull in air and remove moisture using many of the same techniques as typical dehumidifiers.

However, removal of the moisture uses a different strategy. Household dehumidifiers have a reservoir that needs to be emptied on a regular basis, but crawl-space dehumidifiers usually have an attached hose that removes the water away from the house.

moisture and humidity build-up

Why is a Crawl Space Dehumidifier Important?

A crawl-space dehumidifier is essential for any home because it will reduce the moisture under your home and, because of the stack effect, the humidity levels inside your home.

If you are allergic to mold spores, for example, having this type of dehumidifier can reduce your chances of having issues with your allergies. Even healthy people who simply want to avoid exposure to high humidity and want to reduce the chances of mold and mildew growth in their home will find value in this product.


Encapsulation is Essential to Performance

An important part of the overall performance of your crawl space dehumidifier is proper encapsulation of all square feet in the crawl space.

Essentially, this means that you want to create a moisture barrier around the perimeter of your crawl space, which is done with durable plastic materials and other products. Many homes will need an underlay that protects the plastic from sharp objects like stones. Once the underlay is in place, you can lay down the plastic sheeting to keep moisture from seeping upward. This is another step that helps your crawl-space dehumidifier perform at the level you need so you can keep your home dry.


How Is a Crawl-Space Dehumidifier Installed?

Installation of dehumidifiers can be difficult, particularly in crawl spaces with a low overhead. However, when completed properly, a crawl-space dehumidifier will enhance your entire home and should provide reliable performance for years to come.

Your dehumidifier should be placed somewhere near the center of the space to create balanced dehumidification. It should also be placed in an area where the discharge of collected water will not be blocked or slowed in any way.

Some crawl spaces are not perfectly rectangular and may require ducting to evenly pull moisture from the entire area. Many products have an optional ducting kit that can be used to pull air from certain areas.

For example, if you have a U-shaped crawl space that wraps around three of the four sides of the home, you can use ducts to pull air and moisture from each end the U, ensuring balanced dehumidification for all square feet. If your crawl space is divided by a wall, you can extend ducts to one end so your unit pulls air and dehumidifies both sides.

Whether you are mounting the unit to the joists above or placing on the ground, be sure the dehumidifier is level so it gives ideal performance and longevity.


Costs of a Dehumidifier

While dehumidifiers can save you a lot of trouble (and potentially save money by reducing the chances of repair bills), they do come with a cost.

According to HomeAdvisor, the purchase and installation of a crawl-space dehumidifier has a national average of $2,050. (as of Feb 2019.) On the low end, you can spend as little as $1,300, while the high-end models cost roughly $2,800.

Those numbers, however, are the just initial costs. You’ll also add to your energy bill when you use a crawl-space dehumidifier. The overall amount will depend on how much the unit is used, as well as the utility prices in your area, but CostHelper says that they usually cost about $2 to $35 a month to operate.


Learn More About Enhancing Your Home’s Air Quality

If you are interest in proper air quality for your home, contact the helpful staff at Oransi. We’ll help you find the right products, including air purifiers that remove many of the harmful substances found in your home’s air.