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Open Crawl Space Vents

Old building code dictated crawl space vents be installed to allow air to flow in and out. We now know this simply doesn't happen. Instead, outside air is trapped beneath floors where it finds its way into the living areas of the home. It's best to seal vents if your home currently has them.

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Around the 1950s, every home with a crawl space was built with vents. It was believed that the vents would help the stale, stagnant air exit the crawl space. The thinking was that the fresh air circulating in the crawl space would therefore prevent mold growth. However, over the years it has been proven that these vents caused more damage than good.   

If your home has vents in the crawl space, you might be wondering what to do with these openings. Should you leave them be or seal them? A lot of homeowners are struggling with this dilemma. Read on as we address crawl space vents, their purpose, the problems they often cause, and ways to avert these issues. 

What Are Crawl Space Vents?  

Crawl space vents are fixtures that can be found on foundation walls. They at one point were even required by building codes in many areas.   

While crawl space vents are a great idea in theory and should keep the space beneath your home dry and mold-free, they actually cause a whole range of problems. The issue with these fixtures is that they allow wet air to enter the crawl space, which is rather counterproductive as they were invented to help dry out crawl spaces.   

Vents also encourage the airflow from the bottom to the top of the home. In other words, the air from the crawl space eventually ends up in your living area. If the crawl space is full of mold spores, dust and allergens, all those particles find their way to the rest of your home, contaminate the air you breathe, and even cause health problems. 

Disadvantages of Open Crawl Space Vents  

As long your as crawl space vents stay open, there’s no way you will be able to control moisture. Moist air will flow in day and night, and this will drive up humidity levels and set the stage for moisture problems.  

Condensation will follow sooner than you expect. This can lead to damp walls, and worse, wood rot. Your damp crawl space will become a magnet for pests and wood-damaging insects like termites. That’s not to mention mold and mildew that thrive in moist conditions.  

Almost 50% of the air inside your house comes from the crawl space via vents. If the space is dirty, wet, and moldy, you can expect the air that comes up to your living space to be polluted. This toxic air can cause respiratory problems and worsen your asthma.  

When the moisture levels rise in the crawl space, you will experience discomfort while indoors. This will force you to run your heater extensively to warm up your home during winter months, and your AC overtime in the summer to try to keep cool. This also will drive up your monthly energy costs.  

Seal Crawl Space Vents for a Healthier Home  

If you want to make your home energy efficient, deter mold growth, and beat back moisture, plug the crawl space vents from the outside with vent covers. A full seal by the experts at Groundworks can dramatically reduce moisture buildup and temperature fluctuations inside your home.  

Homes that have sealed vents outperform those with open vents. Once you seal the vents, it’s important to encapsulate the crawl space with a heavy-duty at least 20-mil plastic vapor barrier for the ultimate protection.  

Sealing the vents and encapsulating the crawl space has several benefits, including:  

  • Warmer Floors During Winter  
  • 20% Lower Heating Costs  
  • Making It More Difficult For Pests & Termites To Enter
  • Better Indoor Air Quality  
  • Wood Decay & Mold Growth Prevention  

Crawl Space Vent Sealing Help 

Are you concerned with the state or your crawl space? Contact the reliable crawl space experts in your area for a free inspection and quote. We are happy to seal your open vents and encapsulate your crawl space so outside air or moisture won’t trouble you again.  

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