1. It prevents moisture and excessive humidity from getting inside and causing problems. Moisture and humidity here are NOT good things, and they can actually contribute to the growth of harmful mold, mildew, and bacteria. It will also rot the floor over time. Seal the space off, and you don't have to worry about it anymore.

2. A sealed crawl space prevents unwanted pests from getting inside the area under the home. Most homeowners don't think about all the critters that could be living under their home, including: termites, roaches, snakes, spiders, rats, mice, skunks, and so on. Nobody wants these pests living out their entire life cycle below their home! This is dangerous and could lead to some really bad indoor air quality.

3. An encapsulated crawl space will improve the property's value. This is good news if the homeowner is considering putting their home on the market in the next couple of years. Prospective home buyers will want to see that the crawl space is already in good shape so that they won't have to worry about it.