Crawl space encapsulation cost

Total cost by source

Published whole-job and per-square-foot ranges, newest page first. Forbes Home's average sits far above the others, and Fixr gives two different ranges on two pages, so compare more than one. Angi, HomeAdvisor, HomeGuide and Forbes rows come from our price database (read September 28, 2026); their sites blocked a re-read on October 22, 2026. Bob Vila's page is from 2022.

Cost by crawl space size

Most guides price by the square foot, so the total follows the floor area. The table multiplies the per square foot ranges from This Old House ($3 to $7, page of March 13, 2026) and HomeGuide ($3 to $10, page of January 14, 2026) by the size. The arithmetic is ours. ThePricer (updated October 9, 2026) publishes the same size ladder as HomeGuide's range.

Cost by component

Each part below is quoted from the page named, with that page's own date. Parts are not meant to be added up: guides define "the job" differently, and drainage quotes can already include the pump.

Vapor barrier (liner)

Sealing vents

Dehumidifier

Insulation

Drainage and sump pump

Extras that change the total

Vapor barrier thickness

No guide we read prices the liner by mil. This Old House prices it in millimeters (4 mm and 20 mm) and recommends at least 6; DOE's weatherization guidance asks for a ground vapor retarder at least 6 mil thick, covering as close to 100% of the ground as possible and running 6 inches up walls, columns and footings (DOE). A thicker, reinforced liner costs more a square foot in material but is a small part of a total dominated by labor.

Labor is 50% to 70% of the total and materials 30% to 50% in This Old House's breakdown, which puts $2,250 to $10,500 of labor on a 1,500 square foot job.

What drives the cost up

• Moisture and condition. This Old House: $3 to $7 a square foot for a basic job, up to $10 for "an extensive moisture problem."
• Standing or seeping water. Drainage ($600 to $1,800 at This Old House), a sump pump, or waterproofing ($2,000 to $7,000 at Fixr).
• Mold, pests and rot. Mold remediation $500 to $4,000 (This Old House); mold and pest removal up to $6,000 (Bob Vila, 2022).
• Size and access. Whole-area work such as the liner and cleaning scales with floor area (Fixr); permits run $100 to $250 and vary by city (This Old House, Bob Vila).
• Insulation type. Batt at $0.60 to $1.10 a square foot against rigid foam board at $2.50 to $3.00 (This Old House).

Cost by region

None of the guides we read publishes a regional price table; Angi publishes city pages, shown in the first table: Houston $4,930 to $14,790, Dallas $5,155 to $15,465, Austin $4,905 to $14,715 and Columbus $4,775 to $14,325 (May 2026). Climate matters more than the price list: Bob Vila says encapsulation is a better investment in humid regions than in dry ones, where it "likely won't make a difference."

In our county data, 275 of 3,122 rated US counties combine a shallow water table (USDA soil survey) with at least 50 inches of rain in an average year (NOAA 1991-2020). Those are the places where drainage and a dehumidifier are most likely to be on the quote. The crawl space encapsulation guide lists the wettest counties, and the soil by ZIP code lookup shows yours.

DIY or professional

No guide publishes a DIY total. The one DIY number you can build from the published ones is the liner: at This Old House's $0.40 to $0.60 a square foot for 20 mm material, a 1,000 square foot crawl space is $400 to $600 before tape ($18 to $50 a roll), our arithmetic.

This Old House says a handy homeowner can do it but warns DIY "risks trapping moisture and making the problem worse," and recommends professionals for drainage and dehumidifier wiring, who usually offer warranties. Bob Vila (2022) says a DIY job gets no warranty. Contractors add about 10% to the materials they buy for you (Bob Vila).

Before you sign

Get at least three written quotes that list the liner thickness, how many vents are closed, the dehumidifier model and whether drainage is included. The crawl space moisture guide covers the humidity target, and sump pump cost and basement waterproofing cost cover the drainage line.

Questions people ask

How much does crawl space encapsulation cost?

Most cost guides put a whole job at $5,000 to $15,000. Angi, HomeAdvisor and This Old House each give an average of $5,500; This Old House shows a full range of $1,500 to $15,000 and Forbes Home (2024) an average of $15,750 with a range up to $30,000.

How much does crawl space encapsulation cost per square foot?

This Old House gives $3 to $7 a square foot for a basic job and up to $10 for a crawl space with an extensive moisture problem. HomeGuide gives $3 to $10 and Fixr $2 to $6.

How much does it cost to encapsulate a 1,000 square foot crawl space?

This Old House gives $3,000 to $7,000 for 1,000 square feet. Bob Vila (2022) gave $2,000 to $4,000. Multiplying the per square foot ranges by size, a 1,500 square foot crawl space is $4,500 to $10,500 at This Old House rates.

How much does a crawl space dehumidifier cost?

Installed prices run $750 to $3,000 across the four guides we read: $800 to $2,000 at This Old House, $750 to $1,700 at Fixr, $800 to $1,200 at Bob Vila (2022) and $1,000 to $3,000 at ThePricer.

Can I encapsulate a crawl space myself?

You can, but no guide publishes a DIY total. This Old House says a handy homeowner can do it, warns that mistakes can trap moisture, and recommends professionals for drainage and dehumidifier wiring. At its $0.40 to $0.60 a square foot for 20 mm liner, material for 1,000 square feet is $400 to $600 before tape and a dehumidifier.