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open vent in crawl space

Should Crawl Space Vents Remain Opened or Closed?

The longtime debate of whether crawl space vents should be open or closed is settled here. Read on to learn why vented crawl spaces are bad for your home, and how you can fix the problem.

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open vent in crawl space

When it comes to crawl space vents open or closed, the big debate doesn’t want to go away. However, the right answer is very clear. Your crawl space vents should always be closed and sealed off from the outside elements.

Venting your crawl space leads to a variety of issues. First and foremost, open vents allow moisture to enter your crawl space. This creates the perfect environment for mold growth and mildew. Furthermore, unsealed vents could lead to wet insulation, wood rot, and higher electricity bills at the end of the month.

stack effect

Crawl Space Vents Open or Closed: Stack Effect

How does this happen? To clarify, air is typically cooler in your crawl space than it is outside. Once the outside air enters your crawl space and combines with the cooler air, humidity is created. As you can see, combining the two creates moisture problems, which is your crawl space’s greatest foe.

To make matters worse, the warm air that enters your crawl space will rise into the living areas of your home, dragging anything light enough to travel with it. This includes mold spores, dust mites, and the humidity that’s already wreaking havoc in your crawl space. This process is known as the stack effect, and it’s a continuous cycle that will cause a variety of problems for your home and family.

Crawl Space Vents Open or Closed: Energy and Encapsulation

The crawl space vents open or closed debate shouldn’t be a debate at all. Make sure to have your vents closed off properly. Not only is this a stress-free installation process, but the vent covers will be permanently placed over your old vents.

Made from a durable plastic, our vent covers won’t rot or rust. Moreover, they’ll help save you money in the long run. As mentioned before, the outside air causes humidity and moisture problems in your crawl space, which increases energy costs for homeowners.

Nevertheless, moisture problems can be caused by a variety of issues in your crawl space. To further protect your foundation, a crawl space encapsulation will do the trick. This process includes closing off your vents and doors, but it also involves installing a sump pump, a vapor barrier, and bringing in a dehumidifier.

before crawl space encapsulationafter crawl space encapsulation

With this in mind, crawl space encapsulation will NOT work without closed vents. The entire system is in jeopardy if your crawl space isn’t sealed off from the outside air correctly. Open vents create high levels of moisture, condensation, and humidity that will be detrimental to your home’s foundation.

According to a study by Advanced Energy, closed crawl space homes have used an average of 15% less energy for space conditioning. Is that something you may be interested in? If so, contact JES to set up your free, no-obligation inspection. In conclusion, it’s fair to say the crawl space vents open or closed debate has reached its solution, and at JES, we’ll work with you to provide the proper repairs for your home’s crawl space moisture problems.

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