Climate Zone 6 Insulation Guide
Very cold climate covering the northern tier states. Long cold winters with 6,000–8,000+ heating degree days.
R-Value Requirements
Very cold winters. Heating season can span 6–7 months. Maximum insulation levels provide the best ROI.
Locations in Climate Zone 6
Major cities: Minneapolis, Milwaukee
States primarily in Zone 6:
Typical Insulation Scenarios
These estimates are for a 1,200 sq ft attic in Climate Zone 6.
| Existing R | Target R | Recommended Material | Estimated Cost |
|---|---|---|---|
| R-0 | R-60 | Blown-in Cellulose | $2,200–$3,200 |
| R-19 | R-60 | Blown-in Fiberglass | $1,800–$2,600 |
| R-38 | R-60 | Blown-in Mineral Wool | $1,400–$2,200 |
Insulation Depth Required for R-60
| Material | R-Value/Inch | Depth for R-60 |
|---|---|---|
| Blown-in Fiberglass | ~2.5 | ~24" |
| Blown-in Cellulose | ~3.5 | ~18" |
| Blown-in Mineral Wool | ~3.15 | ~20" |
| Open-Cell Spray Foam | ~3.6 | ~17" |
| Closed-Cell Spray Foam | ~6.5 | ~10" |
Frequently Asked Questions
What R-value is required in Climate Zone 6?
The IECC code minimum is R-60. ENERGY STAR recommends R-60. If your existing insulation is below R-60, upgrading will typically pay back within 5–10 years.
Can I add insulation on top of existing insulation?
Yes — in most cases you can add blown-in insulation directly on top of existing batts or blown-in material. No need to remove old insulation unless it is damaged or contaminated. Air sealing any gaps first maximizes the benefit.
How do I know what climate zone I am in?
Enter your zip code in our calculator and it will automatically determine your climate zone and recommend the correct R-value target for your location.
Calculate for Your Zone 6 Home
Enter your zip code for a precise material recommendation and cost estimate for your attic.
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