Insulation R-Value Guide

Get DOE-recommended R-values for attics, walls, and floors in your climate zone, plus insulation material types and the thickness needed to reach target R-values.

Climate Zone (DOE) Home Type

R-value Attic

R-value Walls

R-value Floor

Insulation Materials Guide

Fiberglass battsR-3.1 to R-3.7 per inch

Blown celluloseR-3.2 to R-3.8 per inch

Open-cell spray foamR-3.5 to R-3.8 per inch

Closed-cell spray foamR-6.5 to R-7 per inch

Rigid foam board (XPS)R-5 per inch

Attic depth needed-