Vented vs. Unvented Crawl Spaces: What You Need to Know

Think of the crawl space as another room in your home, similar to a basement. A damp, musty crawl space can be more than just an area you avoid if not properly cared for, as these spaces have a direct impact on indoor air quality and the health of a home. To protect a property and its inhabitants, experts like those at Complete Insulation recommend crawl space encapsulation. Before beginning such a project, however, it’s important to understand whether your crawl space is vented or unvented. Here’s what you need to know about each type:

Vented Crawl Spaces

A vented crawl space is built with multiple foundation vents located in the perimeter walls. These vents allow outside air into the crawl space area. The traditional belief was that venting with outside air would help control moisture and improve overall air quality within the space. However, in reality, vented crawl spaces often lead to moisture buildup, especially in humid regions like the Southeast. This can cause various issues, including mold growth, structural damage, and poor indoor air quality.

Unvented (Conditioned) Crawl Spaces

An unvented, or conditioned, crawl space does not have vents and is sealed against outside air infiltration. Encapsulation is a common method used to create an unvented crawl space. This involves insulating the perimeter walls—instead of the crawl space ceiling—and installing a true vapor barrier to protect against ground-generated water vapor. Proper sealing of the vapor barrier at seams and edges is crucial to prevent vapor penetration, which is why hiring a professional company you can trust is so important. Additionally, a dehumidifier can be installed to maintain optimal humidity levels.

The Benefits of Converting a Vented Crawl Space

Complete Insulation is your go-to company for crawl space encapsulation and insulation in Middle Tennessee. Our decades of expertise in crawl space systems and innovative processes ensure that you receive the best service tailored to your needs, allowing you to enjoy the benefits of converting your vented crawl space into an unvented, conditioned one. These benefits include:

  • Improved energy efficiency – By insulating the perimeter walls and sealing off the space, an unvented crawl space reduces energy loss, leading to lower heating and cooling costs.
  • Moisture control – Encapsulation prevents outside moisture from entering, significantly reducing the risk of mold, mildew, and wood decay.
  • Enhanced air quality – Sealing the crawl space helps keep out pollutants and allergens, improving the overall air quality in your home.
  • Structural protection – By controlling moisture levels, encapsulation helps protect the structural integrity of your home, preventing damage to floor joists and other components.
  • Pest prevention – A sealed crawl space is less inviting to pests like rodents and insects, reducing the likelihood of infestations.

When you partner with us for your project, you can expect exceptional service from start to finish. We use top-of-the-line materials like TRU-Encap and VIPER CS 10ML reinforced poly vapor barriers to ensure the highest quality encapsulation.

Get Your Crawl Space Encapsulation Project Started

Let Complete Insulation be your trusted partner for all your crawl space insulation and encapsulation needs. Reach out to us today and discover the difference a professional, unvented crawl space can make in your home. We’d be happy to tell you more about the difference between vented and unvented crawl spaces and to show you why we’re the go-to insulation service company in Nashville, TN, and beyond.

“I was building my own custom home and "interviewed" several spray foam insulators. It was clear Moody Ozier had a deeper knowledge of air sealing, R-value, and building codes than anyone else, so I went with Complete Insulation. He really took an interest in my hyper efficient build and came up with additional engineering ideas to further improve the efficiency of my home. I cannot say enough good things about Moody and Id tell anyone he's trustworthy, efficient, and knows the insulation and air sealing business to great depth. Jose, Fredy, and their crews showed up on time, in uniforms, with clean trucks and did a wonderful job on instal AND cleanup. They were incredibly professional at every step and it was clear they had years of experience. I recommend Complete Insulation to anyone with encapsulation and/or insulation needs whether you are new construction, retro fit, investor, or otherwise.”

Chad Kozloski
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“I had a fire in my attic and needed all of the contaminated insulation removed. I am *AMAZED* at how thorough the hard working folks at Complete were. You could almost eat off the floor of the attic. The entire crew was courteous, quick and more than fair with the price. Highly recommend.”

- Derek Hinz

“The team who came from Murfreesboro, TN to our house in Chattanooga were amazing. We have a very large home. They removed all the old insulation from our three attics, sprayed with a decontaminate and then sprayed all the new insulation. All in one very long day. They were great to work with, came went they said they would, answered all our questions. Had to put the tubes all the way from the attic down to the first floor and out to the truck. They covered all the floors, stairs etc and left the place spotless. We are very pleased and would highly recommend this company.”

- Lorraine Forman

“I was building my own custom home and "interviewed" several spray foam insulators. It was clear Moody Ozier had a deeper knowledge of air sealing, R-value, and building codes than anyone else, so I went with Complete Insulation. He really took an interest in my hyper efficient build and came up with additional engineering ideas to further improve the efficiency of my home. I cannot say enough good things about Moody and Id tell anyone he's trustworthy, efficient, and knows the insulation and air sealing business to great depth. Jose, Fredy, and their crews showed up on time, in uniforms, with clean trucks and did a wonderful job on instal AND cleanup. They were incredibly professional at every step and it was clear they had years of experience. I recommend Complete Insulation to anyone with encapsulation and/or insulation needs whether you are new construction, retro fit, investor, or otherwise.”

- Chad Kozloski