Planning a home project in Illinois? This page brings together every cost guide we publish for the state — installed prices, yearly savings and payback for 2026 — plus the verified Illinois rebate programs that can cut the bill.
In Illinois, the swing seasons and real winters and summers shapes the energy year, and installation work here runs about 8% above the national average — both are built into every range below.
Published Illinois Guides
Home Project Costs in Illinois at a Glance
| Project | Typical cost in Illinois | Yearly savings | Simple payback | Guide |
|---|---|---|---|---|
| Central AC Replacement | $5,350–$10,700 | $335 | 24.0 years | Coming soon |
| Heat Pump | $7,150–$17,100 | $810 | 15.0 years | Read the guide |
| Attic Insulation | $1,500–$3,400 | $440 | 5.6 years | Coming soon |
| Roof Replacement | $8,350–$20,000 | $60 | — | Coming soon |
| Solar Panels | $15,150–$22,500 | $1,415 | 13.3 years | Coming soon |
| Tankless Water Heater | $2,850–$5,250 | $115 | 35.2 years | Coming soon |
| Replacement Windows | $6,450–$13,400 | $330 | 30.1 years | Coming soon |
Verified Rebates & Incentives in Illinois
- ComEd / Ameren Illinois Heat Pump Rebate — Up to $1,400 for qualifying heat pumps. ComEd or Ameren Illinois customers; cold-climate models earn the top amounts. Covers: Heat Pump. Source: HomeUpgradeCheck state rebate index
- Illinois Shines — Solar Renewable Energy Credit payments worth roughly $65-$85 per MWh, contracted for 15 years. Paid through the Illinois Shines Adjustable Block Program via your installer or an aggregator. Covers: Solar Panels. Source: Illinois Shines (via 2026 solar incentive roundup)
Amounts and rules change — confirm eligibility with the program before you sign a contract, and note that several programs require action before installation.
Figures compiled from public sources, updated October 2026. Local quotes vary — get 2–3 estimates.