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Moisture control · Most requested

Crawlspace encapsulation

Seal out humidity, control groundwater, improve indoor air quality.

Encapsulation seals your crawlspace with a heavy-duty vapor barrier to keep out moisture, humidity, and pests — improving air quality and protecting your home's structure. In a Tennessee summer, a vented crawlspace pulls humid outside air into the coolest part of your house, and that moisture ends up in your framing, your ductwork and the air you breathe upstairs.

Call 931-650-5859Book my free inspection
1–3 daysTypical project
FreeInspection & estimate
WarrantyMaterials & labor
YearlyService included
Signs you need it

How do I know if I need crawlspace encapsulation?

Signs include musty odors, high humidity, mold growth, standing water, sagging floors, or increased allergy symptoms.

Most of these show up upstairs before anyone crawls under the house. Air moves upward through a home, so whatever is in the crawlspace is being pulled into the living space above it — which is why a moisture problem under the floor often reads as an air quality problem in the bedrooms.

  • Musty odors in closets, hallways or on the first floor
  • High humidity — the house feels damp even with the AC running
  • Mold growth on joists, subfloor or ductwork
  • Standing water after rain, or ground that never dries out
  • Sagging floors — often the first structural consequence
  • Increased allergy symptoms that ease when you leave the house
What a full system includes

Encapsulation is a system, not a sheet of plastic

A liner laid over wet ground traps the problem instead of solving it. Groundwater comes first, then the seal, then humidity control. Your estimate lists each piece separately so you can see exactly what you're buying.

  1. Clean-out & prep

    Debris, old failed plastic, and construction leftovers come out. We grade the soil surface so the liner sits flat and drains where it should.

  2. Groundwater control

    Where water enters, interior drainage and a sealed sump move it out before anything gets sealed over. Grading and downspout problems get flagged in the report.

  3. Heavy-duty vapor barrier

    Reinforced liner across the floor and up the walls, seams sealed, terminated and fastened around every pier and penetration — not loose-laid poly.

  4. Vents & penetrations sealed

    Closing the vents is what stops humid outside air from being pulled in. Plumbing, wiring and duct penetrations get sealed at the same time.

  5. Dehumidification

    A sealed space still needs its humidity managed through a Tennessee August. We size the unit to the volume and hard-plumb the condensate so there's no bucket to empty.

  6. Structural repairs first

    Rotted posts, damaged joists or a sagging floor get addressed before the space is closed up — no one wants to reopen a finished crawlspace.

See floor support systems
How the job runs

Four steps, and you see the findings before the price

  1. Free inspection

    We go under the house, take moisture readings, check every support, and run a FoundationScan® to map the floor. Takes as long as it takes.

  2. Findings & written estimate

    Photos, readings and the scan report, walked through with you — then a line-item price. Financing options if you want them.

  3. Install

    Most crawlspace projects run 1–3 days. Same family crew that quoted the job does the work.

  4. Annual service

    We come back every year to service the equipment we installed and re-run the scan. No long term contract required.

Cross-section of a fully encapsulated crawlspaceSide-on cut through a house crawlspace. Above the void, carrying the first floor of the house: the subfloor, the floor joists shown in section, and the girder they bear on. Below and around it: a masonry block perimeter wall on each side standing on a poured footing, one existing full-height masonry pier, and the earth. The outside ground level is well above the crawlspace floor, which is how groundwater gets in. Six numbered parts, all drawn in orange, are the system DrySpace installs. 1, structural repairs: a new adjustable support post on a pad footing, carrying a replaced section of girder. 2, clean-out: debris and old failed plastic, drawn as a dashed ghosted pile marked removed. 3, groundwater control: a perforated drain line beside the footing feeding a sealed sump basin at the low point, with a discharge line running up and out through the wall, and arrows showing groundwater moving toward the sump. 4, heavy-duty vapor barrier: a liner across the whole floor, run up both walls and up each pier, terminated on a fastened bar below the vent line. 5, vents sealed: the block wall vent plugged, with an arrow showing humid outside air stopped at it. 6, dehumidification: a dehumidifier standing on the liner inside the sealed space. Everything already under the house is navy or grey; everything DrySpace adds is orange.FIRST FLOOR ABOVEHUMIDOUTSIDE AIRGIRDERPIERREMOVEDSUBFLOORJOISTSBLOCKWALLFOOTINGGROUNDWATEREARTH123456
  • House framing
  • Block, footings & earth
  • What DrySpace installs
  1. Structural repairs first — Rotted posts, damaged joists or a sagging floor get addressed before the space is closed up.
  2. Clean-out & prep — Debris, old failed plastic and construction leftovers come out, and we grade the soil so the liner sits flat.
  3. Groundwater control — Where water enters, interior drainage and a sealed sump move it out before anything gets sealed over.
  4. Heavy-duty vapor barrier — Reinforced liner across the floor and up the walls, seams sealed, terminated and fastened around every pier and penetration.
  5. Vents & penetrations sealed — Closing the vents is what stops humid outside air from being pulled in; plumbing, wiring and duct penetrations get sealed at the same time.
  6. Dehumidification — We size the unit to the volume and hard-plumb the condensate, so there is no bucket to empty.

Illustration of the encapsulation system — not a photograph of a specific job.

What changes afterward

You notice it upstairs, not under the house

  • Better indoor air qualitySealing off mold, soil gases and damp air below the floor changes the air in the rooms above it.
  • The musty smell goes awayAnd it stays gone, because the moisture feeding it no longer has a way in.
  • Framing stops absorbing waterControlled humidity is what stops wood rot before it becomes a floor repair.
  • HVAC works lessYour system stops fighting humid air pulled from under the floor.
  • Pests lose the habitatDry, sealed crawlspaces are far less attractive to rodents, insects and termites.
FAQ

Crawlspace questions

What is crawlspace encapsulation?

Encapsulation seals your crawlspace with a heavy-duty vapor barrier to keep out moisture, humidity, and pests — improving air quality and protecting your home's structure.

How do I know if I need crawlspace encapsulation?

Signs include musty odors, high humidity, mold growth, standing water, sagging floors, or increased allergy symptoms.

How long does a typical project take?

Most crawlspace and waterproofing projects are completed in 1–3 days. Larger foundation repairs may take longer depending on the scope.

Are your services guaranteed?

Yes. All of our work is backed by warranties on both materials and labor for peace of mind.

Do you offer free inspections or estimates?

Yes. We provide free, no-obligation inspections and written estimates for all of our services.

Free crawlspace inspection

We'll go under the house, show you photos of what's actually down there, and price the work in writing. No cost, no obligation.

Call or text 931-650-5859

Family owned & operatedFree estimatesFinancing as low as 0%Annual inspections included