Document the condition
Record where it appears, when, whether storms or tides seem connected, and how it's changed. Photos and rough measurements make the first conversation easier.
Read the local context
Establish the parcel's flood status before anything is sealed, because on a property in a mapped flood zone an enclosure below the flood elevation is expected to let water in and out through vents -- so this is a regulatory question before it is a performance one. Then get underneath and look: the depth, the ground cover, the state of the insulation and whether standing water is present. Sandy soil drains at the surface, so a wet crawl space here more often points at the shallow water table or at humid air than at grading.
Ask what will be hidden
Good planning traces bulk water paths, low spots that collect moisture, clearance for termite inspectors, a properly sealed and fastened liner, air sealing at the band joist, correctly sized dehumidification, and the current condition of the floor framing. Because the liner conceals the prep work once installed, the written scope should describe exactly what was checked and done first.
Compare complete scopes
A solid scope spells out protection, access, materials, permits, testing, cleanup, restoration, exclusions, warranties, and change-order pricing.
What official local sources add
Of everything in that list, the high water table is what governs a Wilmington crawlspace. On low coastal ground the soil beneath a house is damp for much of the year regardless of rainfall, which is why a liner alone rarely holds conditions here and why dehumidification is part of the system rather than an upgrade to it. Salt-laden air adds a second load on any metal fastener or duct under the floor. In a local historic district, note that foundation vents and their treatment are exterior features that review can reach.
Reviewed June 2026 -- confirm your specific parcel's flood zone, historic-district status, permit requirements, and current rules with the relevant authority before authorizing work.