Crawl Space Insulation Calculator

Insulation type and R-value for crawl space encapsulation.

Crawl space area

sq ft

Perimeter length

Wall height

Insulation approach

Material

Target R-value

Tab to move between fields

Insulation thickness

9.55 in

≈ 3 credit cards

Total project cost

$6,706.00

≈ 7 smartphones

Insulation area800 sq ft

Vapor barrier area800 sq ft

Insulation material cost$2,293.00

Vapor barrier cost$400.00

Est. annual savings$225.00

How to Use This Calculator

Enter Crawl space area, Perimeter length, and Wall height.
Set Insulation approach, Floor insulation (vented crawl), and Wall insulation (encapsulated).
Adjust Material, Fiberglass batts (R-3.14/in) as needed.
Review Insulation thickness (in) and Total project cost ($).
Use Insulation area (sq ft) and Vapor barrier area (sq ft) to inform your decision.

How the result changes with Target R-value

Crawl space area: Total crawl space floor area.
Perimeter length: Total perimeter of crawl space walls.
Wall height: Height of crawl space walls from footer to sill plate.
Insulation approach: Vented crawl: insulate floor above. Encapsulated: seal and insulate walls.
Material: Insulation material. Rigid foam and spray foam are typical for encapsulation.
Target R-value: Desired R-value. IRC code typically requires R-19 to R-30 for floors/crawl walls.

Insulation thickness: Required depth of insulation material.
Insulation area: Total surface area to insulate.
Vapor barrier area: Area of vapor/moisture barrier needed.
Insulation material cost: Cost of insulation material alone.
Vapor barrier cost: Cost of vapor barrier (6-mil poly or 20-mil encapsulation liner).
Total project cost: Estimated total including materials and labor.
Est. annual savings: Estimated yearly heating cost reduction.

Identify Input Parameters
4 parameters
Crawl space area = 800, Perimeter length = 120, Wall height = 3, Insulation approach = 0 = 6 input(s) provided
Calculate Insulation thickness
Insulation thickness = targetRValue / rPerInch
9.55 = 9.55
Calculate Total project cost
Total project cost = totalMaterialCost + laborCost
6706 = $6,706
Calculate Insulation area
Insulation area
800 = 800
Calculate Vapor barrier area
Vapor barrier area
800 = 800