Insulation R-Value Calculator | EZ Virtual Tools Construction

Code R-Value Requirements

Climate Zone

Building Type

IECC 2021 Requirements

R-0
Ceiling/Attic

R-0
Wall Cavity

R-0

Wall CI

continuous

R-0

Floor

R-0

Basement Wall

R-0

Slab Edge

Climate Zone 4: Includes marine and mixed-humid regions. Wall CI may be traded for higher cavity insulation in some cases.

Calculate Insulation Quantity

Area to Insulate (sq ft)

Insulation Type

Target R-Value

Waste Factor %

Material Estimate

0
Batts/Bags
--

Thickness

minimum

0.0

R per Inch

Total Area

sq ft

Coverage

sq ft/unit

Compare Insulation Types

Target R-Value

Thickness Comparison

Type	R/Inch	Thickness	Notes

IECC 2021 Residential R-Value Requirements

Zone	Ceiling	Wall	Floor	Basement	Slab
1	R-30	R-13	R-13	R-0	R-0
2	R-38	R-13	R-13	R-0	R-0
3	R-38	R-20 or 13+5ci	R-19	R-5ci	R-0
4	R-49	R-20 or 13+5ci	R-19	R-10ci	R-10
5	R-49	R-20+5ci or 13+10ci	R-30	R-15ci	R-10
6	R-49	R-20+5ci or 13+10ci	R-30	R-15ci	R-10
7	R-49	R-20+10ci or 13+15ci	R-38	R-15ci	R-10
8	R-60	R-20+10ci or 13+15ci	R-38	R-15ci	R-10

ci = Continuous Insulation. R-values shown are for wood-frame construction. Mass walls and steel frame have different requirements. Always verify with local code.