R-Value by USDA Climate Zone
Recommended R-value for wall and roof envelope of agricultural buildings, by IECC / DOE climate zone, with matching Ag-Tite foam thickness and documented savings range.
All US climate zones — at a glance
| Zone | Description | Wall R | Roof R | Typical savings |
|---|---|---|---|---|
| 2A | Hot-humid (2A) — FL, TX (south), LA | R-13 | R-30 | 18%–28% |
| 3A | Warm-humid (3A) — GA, AL, SC, AR, NC (east) | R-15 | R-38 | 22%–32% |
| 4A | Mixed-humid (4A) — NC (west), TN, KY, VA | R-19 | R-49 | 25%–38% |
| 5A | Cool-humid (5A) — IA, IN, OH, PA, NY | R-21 | R-49 | 28%–40% |
| 6A | Cold (6A) — MN, WI, MI, ND, SD | R-21 | R-60 | 30%–42% |
| 7 | Very cold (7) — MT, ME (north), parts of MN | R-21 | R-60 | 32%–45% |