Windows vs. Insulation: Which Provides Better ROI?

Limited budget? According to the U.S. Department of Energy, how you prioritize home efficiency improvements dramatically affects your return on investment.

The ROI Comparison

According to DOE and ENERGY STAR data:

| Improvement | Typical Cost | Annual Savings | Payback |
|-------------|--------------|----------------|---------|
| Attic insulation (R-30 to R-49) | $1,500-2,500 | $200-400 | 5-10 years |
| Air sealing | $300-1,000 | $100-300 | 2-5 years |
| Window replacement (10 windows) | $5,000-10,000 | $100-200 | 30-70 years |

The math strongly favors insulation and air sealing for pure energy ROI.

Why Insulation Often Wins

According to Lawrence Berkeley National Laboratory:

1. Lower cost per R-value: Insulation is cheap compared to windows
2. Larger surface area: Your attic and walls have more area than windows
3. Air sealing bonus: Insulation work often includes air sealing
4. Already replaced single-pane: Most homes already have double-pane

When Windows Make Sense First

According to DOE guidance, prioritize windows when:

• You still have single-pane windows (rare today)
• Windows are severely damaged or failing
• Comfort issues are window-specific (drafts, cold glass)
• You're renovating anyway (economies of scope)
• Insulation is already adequate

The Recommended Approach

According to the U.S. Department of Energy, the optimal order for most homes:

1. Air sealing - Biggest bang for buck
2. Attic insulation - If below R-49
3. Wall insulation - If accessible
4. Windows - After envelope is addressed

The Bottom Line

From a pure energy savings perspective, insulation and air sealing typically provide better ROI than window replacement. But windows offer comfort, noise, and aesthetic benefits that insulation doesn't.

Consider your priorities: pure energy savings, or a combination of efficiency and home improvement?

*For complete analysis, see: [Window Energy Savings Analysis](/guides/window-energy-savings-analysis)*