Insulation Calculator for Crawl Spaces
Estimate insulation packages for a crawl space.
Crawl spaces are insulated either between the floor joists above or on the perimeter walls, commonly around R-19. Measure the area you're insulating and enter the package coverage below.
Insulation Calculator
Estimate how much you need — and the cost.
- sq meters 9.75
Tip: In damp crawl spaces, pair insulation with a vapor barrier so the batts stay dry and effective.
How it's calculated
Batt and roll packages list the area they cover — often 40–90 sq ft depending on R-value and width. Packages = area × (1 + waste) ÷ coverage per package.
See the full Insulation Calculator for the complete how-to, unit conversions, and data sources.
Insulation Calculator for Crawl Spaces FAQ
What R-value for a crawl space?
Around R-19 is common for crawl-space floors or walls, but the right value depends on your climate zone and code.
How much insulation for a crawl space?
Measure the floor or wall area you are insulating and divide by the coverage per package entered above.