Crawl Space Encapsulation Cost Calculator

Estimate a crawl-space encapsulation from the liner area — floor plus the walls you line — times the price per square foot from your quote, with room for a dehumidifier, sump and drainage.

Planning estimate: this is a planning estimate from the numbers you enter and standard reference quantities — not a bid or a contract. Get itemized written quotes from licensed contractors and confirm measurements before you commit.

Calculator

sq ft
Length × width of the crawl-space floor.
LF
Total length of the crawl-space walls you will line.
ft
How far the liner runs up the wall (often 3 ft).
$/sq ft
From your quote — liner material plus labor. Example figure.
$
Optional extras you were quoted; leave 0 to skip.
Estimated total$8,340.00
Liner area1,390 sq ft (floor 1,000 + walls 390)
Liner$8,340.00 (× $6.00/sq ft)
Add-ons (dehumidifier/sump/drainage)$0.00

Encapsulating a 1,000 sq ft crawl space (plus 390 sq ft of walls = 1,390 sq ft of liner) at $6.00/sq ft is about $8,340.00 with your add-ons.

Formula

Encapsulation is priced on the total liner area you cover — the floor plus the walls the liner runs up — times a price per square foot, plus any add-ons:

liner_area = floor_area + (perimeter × wall_height)
total       = liner_area × price_per_sq_ft + add_ons

The wall term (perimeter × wall_height) is why a small-footprint crawl space with tall stem walls can still take a lot of liner. Enter the $/sq ft your contractor quoted — the tool holds no price list.

Worked example

Take a 1,000 sq ft crawl space with a 130 ft wall perimeter lined 3 ft up the wall, at $6/sq ft, no add-ons:

  • Wall liner area = 130 × 3 = 390 sq ft
  • Liner area = 1,000 + 390 = 1,390 sq ft
  • Cost = 1,390 × $6 = $8,340

Add a dehumidifier or sump in the add-ons field to fold those quotes into the same total.

Background & practice

Encapsulation seals the crawl space with a heavy vapor barrier over the floor and up the walls, usually taped and mechanically fastened, sometimes with a dehumidifier and a sump. The number that moves the price most is the liner area, so measure the floor and the wall run carefully before you compare quotes. Thicker liners (higher mil), extra fastening, insulation and drainage all push the $/sq ft up — enter the figure for the exact scope you were quoted.

Encapsulation is a moisture-and-air control project, not a structural or health treatment: it does not fix active water pressure on its own (pair it with exterior drainage or an interior system and a sump) and it is not a substitute for a professional mold assessment. If you are turning the space into finished living area rather than sealing it, that is a remodel — see renovationcalcs. See the vapor-barrier coverage table for liner conventions.

Frequently asked questions

How is crawl space encapsulation cost calculated?
It is the total liner area — floor area plus wall area (perimeter × the height the liner runs up the wall) — multiplied by the price per square foot you were quoted, plus any add-ons like a dehumidifier or sump. This tool uses your price, so it never goes out of date.
What is crawl space encapsulation cost for 1,500 sq ft?
Enter 1,500 for the floor area, add your wall perimeter and height, and your $/sq ft. As a worked example, a 1,500 sq ft floor with 150 ft of wall lined 3 ft up is 1,500 + 450 = 1,950 sq ft of liner; at $6/sq ft that is about $11,700 before add-ons.
Does encapsulation include a dehumidifier?
Sometimes. Basic encapsulation is the liner and sealing; a dehumidifier, sump pump or drainage are common add-ons priced separately. Put those quoted amounts in the add-ons field so the total reflects your exact scope.
Should I line the walls as well as the floor?
A full encapsulation runs the liner up the stem walls, which is why the wall term (perimeter × height) is in the formula. A floor-only vapor barrier costs less but seals less; the tool lets you set the wall height to match the scope you want.
Is encapsulation a fix for a wet crawl space?
It controls moisture and air, but it does not relieve active water pressure by itself. If water is entering, pair it with drainage and a sump, and have a professional assess the cause. It is not a mold-remediation or health treatment.

Related calculators

Vapor Barrier CostWork out how many rolls of crawl space vapor barrier you need from your floor area, overlap and roll coverage, times the price per roll you enter.Crawl Space Dehumidifier CostFind the crawl space dehumidifier sizing tier for your area and total the unit and install prices you enter. Moisture control is not a mold assessment.Crawl Space Insulation CostEstimate crawl space wall insulation cost from your wall area and the price per square foot you enter for rigid board or spray foam at your target R-value.Interior Drain Tile CostEstimate interior drain tile cost from your footing perimeter and the price per linear foot you enter, plus the installed sump pump price from your quote.