Licensed & Insured. Crawl space Encapsulation and Mold Remediation

Myth: All vents in the encased crawl space should be sealed.

myth all vents in the encased crawl space should be sealed

All vents in the encased crawl space should be sealed

A sealed crawl space, also known as an encased crawl space, is one in which all vents have been shut and a crawl space vapor barrier has been installed on the walls, floors, and pillars. According to many experts and engineers, this design is one of the greatest ways to construct a healthy crawl space.

The crawl space of many homes contains radon and other soil gases. Soil gases can become more potent in the living space if the crawl space is not adequately vented during encapsulation, much as homes can get excessively humid if an appropriately sized crawl space dehumidifier is not incorporated during encapsulation and sealing the vents. If essential water management or crawl space waterproofing is not performed prior to encapsulation, other homes may flood and float the plastic. When enclosing your crawl space, we recommend that you explore all of these choices to guarantee that it is worry-free for years to come.

Why Sealing the Vents is Important

During crawl space encapsulation, the crawl space vents must be sealed to assist reduce humidity. 

In crawl space encapsulation, proper ventilation is just as critical as humidity management. 

Before entering your living space, ventilation will transfer soil gases and aromas from the crawl space.


The EPA’s website is where I first learned about crawl space ventilation with encapsulation. 

While researching radon, I came across a photo of a single crawl space vent fan pumping air out of an encased crawl space. A dehumidifier was installed and all other vents were sealed. There was also sufficient vapor barrier and crawl space insulation installed.

It seemed logical to me that totally isolating the crawl space without providing adequate ventilation would allow soil 

gases and aromas to infiltrate the living space. Since reading the essay, I’ve been a firm believer in crawl space encapsulation and good ventilation. 

Crawl Space Makeover installs a crawl space foundation fan in every encased crawl space for this reason.


Greg Lewis

Greg Lewis

Greg Lewis is the founder and CEO of Tier Restoration, a company dedicated to restoring the indoor environment of homes and businesses experiencing water damage, smoke damage, or mold contamination.

Greg has spent most of his life working in this industry in Nashville, Tennessee, in the 1970s, working in his father’s commercial cleaning business, in the 1980s and 1990s as a partner with his father in the Sears Carpet and Duct Cleaning franchise, then on his own since 2000.

Greg played his trumpet at Overton High School and the University of Tennessee, Chattanooga, and you can still find him playing throughout the Greater Nashville, Tennessee area.