# Encapsulated Crawl Space Problems (and Why They Happen) > Problems in encapsulated crawl spaces — trapped water, high humidity, failed seams, hidden leaks — and the shortcut behind each one. URL: https://910crawlspacepros.com/guide/encapsulated-crawl-space-problems/ Home / Crawl Space Encapsulation / # Common Encapsulated Crawl Space Problems Reference Common Encapsulated Crawl Space Problems Nearly every one traces back to a specific shortcut. Updated 2 August 2026 The common problems are humidity that never comes down, water trapped under the liner, seams and terminations that release, hidden plumbing leaks and condensation on ductwork. Almost all of them trace to one of two shortcuts: sealing before the water was handled, or sealing without conditioning. ## Humidity that never reaches target Usually an undersized dehumidifier, or a space that is not actually sealed — most often at the access door, which is the largest remaining opening once the vents are done. Check the door seal and the vent detailing before assuming the unit is at fault. ## Water under the liner The classic outcome of encapsulating a crawl space that still takes groundwater. The water has nowhere to evaporate to, and the first symptom is usually an odour months later. The fix is drainage, which now means lifting the liner along the perimeter — considerably more expensive than doing it in the right order. ## Seams and terminations letting go Tape applied to dusty block releases. Liner that was not mechanically fastened at the perimeter slides down. Piers left unwrapped let moisture track up around them. These are workmanship failures rather than design ones, and they concentrate at the edges rather than in the field of the liner. ## Hidden leaks and duct condensation A sealed liner hides a slow plumbing leak that would have been visible on open ground. Inspect twice a year. Uninsulated ductwork in a crawl space that is now semi-conditioned can sweat. If ducts run down there, they should be sealed and insulated as part of the work. ## The bottom line Most encapsulation problems are installation problems. Water first, conditioning always, and terminations done properly — get those right and the failure list mostly disappears. For a number against your own crawl space, use the cost estimator , or call (910) 886-2018 and we will come and measure it. Get an exact quote A free on-site measure beats any online range. Website What do you need? Select a service… Crawl Space Encapsulation Crawl Space Insulation Crawl Space Waterproofing Crawl Space Mold Removal Crawl Space Vapor Barrier Installation Crawl Space Dehumidifier Installation Crawl Space Drainage Crawl Space Sump Pump Installation Crawl Space French Drain Crawl Space Cleanup Crawl Space Structural Repair Sagging Floor Repair Crawl Space Door Replacement Flood Vent Installation Not sure — I need someone to look ZIP code Continue Your name Phone What are you seeing? (optional) Back Request my inspection Got it — your request is in. We'll be in touch with a quote. Related service Crawl Space Encapsulation Related guides The Real Negatives to Crawl Space Encapsulation How Long Does Crawl Space Encapsulation Last? Crawl Space Encapsulation vs. Vapor Barrier Is Crawl Space Encapsulation Worth It? Crawl Space Encapsulation Cost Per Square Foot in Wilmington, NC All guides → , not a heading: this is a CTA, not a section of the document outline. --> Get your crawl space measured and priced Free on-site inspection across Wilmington and New Hanover, Brunswick and Pender counties. Free quotes within 24 hours. Call (910) 886-2018 Get a free quote ## Questions Can an encapsulated crawl space still get mold? Yes, if humidity is not controlled or water is trapped underneath. Sealing alone does not prevent growth; sealing plus conditioning does. How do I know if my encapsulation was done properly? Check the humidity reading, the access door seal, whether the piers are wrapped, and whether the perimeter is mechanically fastened rather than only taped. Those four cover most of it. Should I inspect an encapsulated crawl space? Twice a year. The liner hides slow leaks that would otherwise be obvious, which is the main argument against treating it as a space you never enter again.