Crawl space encapsulation FAQ

Crawl space encapsulation uses a continuous ground and wall vapor retarder, compatible seam tape and sealants, mechanical wall attachments, sealed vents and access doors, and a planned humidity-control method. Drainage, a sump, wall insulation, radon provisions, or a dehumidifier may also be required by the site and local code.

Crawl space encapsulation converts a vented or open-earth crawl space into a deliberately closed, moisture-controlled area. A continuous liner isolates soil moisture, vents and air leaks are sealed, bulk water is managed, and humidity is controlled through an approved conditioning, exhaust, or dehumidification method.

There is no reliable national percentage showing how much crawl space encapsulation increases home value. It can protect marketability by resolving moisture, odor, pest, or inspection concerns, but an appraiser may not add the project cost dollar for dollar and buyers may simply expect the crawl space to be dry.