A crawlspace is a hollow area under the floor of some homes, typically those without basements. It is found between the ground and the first floor of the home and is usually about 1 to 3 feet high. A crawlspace is used to elevate your home off the ground and also provides a convenient place to house parts of the home that are otherwise found in a basement (air conditioning, heater, duct work, insulation, plumbing, and electrical).

Crawlspaces can also pose many health and safety issues for you and your family. Rodents, birds, and other pests can make their way into the crawlspace and nest. Poor insulation of the crawlspace can lead to heat loss in the home. Poor ventilation allows for excess moisture which can propel mold growth. Finally, it allows ample space for dust and other allergens to accumulate. In fact, up to 50% of the air you breathe in your home comes from the crawlspace.

Crawlspace enclosure (or encapsulation) creates a barrier within the crawlspace to insulate against this humidity. It also helps prevents pests from getting in and decreases utility costs. Crawlspace enclosure is increasing in popularity as a home improvement project. How do you know if this is project is right for you? Here are some pros and cons to crawlspace enclosure.


  1. Reduced moisture. Too much moisture provides the ideal environment for mold, mildew and fungus in the crawlspace. High humidity is also a huge attractant for insects and other pests. Crawlspace enclosure provides waterproofing and proper ventilation of the space so the moisture is appropriately and adequately dissipated, reducing the health risks of mold, mildew and fungus.
  2. Pest control. Crawlspaces provide perfect habitats for pests and wildlife to seek shelter from the elements. This can be detrimental to the health and structure of your home. Pests can contaminate the airspace under your home with feces and urine which is then breathed in through the air circulating in your house. They can also chew through wires, pipes, and other structural elements of your foundations, presenting serious safety issues. Crawlspace enclosure provides a shield against these bothersome pests. The airtight barrier prevents animals from breaching the area and provides a layer of protection against termites, rodents, wildlife, and other insects.
  3. Improved air quality. Dust and other allergens can accumulate freely in your crawlspace, aggravating allergies and asthma in those affected members of your family. Crawlspace enclosure helps block these allergens from collecting in the crawlspace area. It can also reduce or eliminate bothersome odors that waft up from the space from mold, mildew, and fungus.
  4. Decreased utility bills. Crawlspaces provide an avenue for cool or warm air from your climate controlled home to seep out into the surrounding environment, making your heating and air system work much harder to keep your home temperature regulated. Crawlspace enclosure helps reduce these costs over the lifetime of the product. Less air is lost through the crawlspace, creating a form of insulation under your home, keeping air in. This also helps protect your heated indoor environment from the cold ground under the home in the winter time and helps maintain a cooler element on your bottom floor in the summer time. Crawlspace enclosure also allows for the installation of a radiant heating system for the floors above it, adding another level of energy efficiency to your home by helping keep each room at a constant temperature.
  5. Extra storage. Crawlspaces are not known as very clean or inviting places. By enclosing the crawlspace, you create a sanitary storage space that can be used in addition to your attic or garage to help declutter your home.


  1. Improper installation. While crawlspace enclosure can be done as a DIY project, it is a very serious undertaking and should be performed with the utmost care. Use of incorrect materials or improper installation can lead to serious problems for the health and safety of the home. Improper installation can cause odors to seep into the house from mold and mildew that accumulates. Excess moisture and humidity is often a byproduct of improper sealing when doing this installation yourself.
  2. Initial cost. The average cost of crawlspace enclosure varies widely depending on which contractor you use, the materials used, the size of the crawlspace, and any additional features you add on. The average installation is between $5000 and $7000 while DIY installations average around $2000. As mentioned above, if you choose to install this yourself, it is critical that you use the proper materials and follow the installation instructions exactly.
  3. Additional maintenance costs. Depending on the features you get with your crawlspace enclosure, additional maintenance and chores each month can add more costs to your initial setup. You may require foundation insulation which is an added cost. Once the crawlspace is enclosed, you may also need to upgrade your HVAC system. Finally, if any wires or pipes run through your crawlspace, the capsule will have to be broken and subsequently repaired each time you need to access those wires and pipes, which can become quite costly over time.

Crawlspace before and after
While there are several disadvantages and benefits of crawlspace enclosure, it is a very sound investment idea and is especially beneficial to homeowners in areas with warm, wet climates. As with any major home improvement project, take the time to do some research into the costs, benefits, and professionals who can provide you with these services. If you are interested in learning more about crawlspace enclosure, request a fee estimate here.