Insulation cost calculator: estimate costs and energy savings

Insulation is one of the few home improvements that pays for itself through lower energy bills. This calculator does more than estimate the cost. Enter your zip code to get R-value recommendations for your climate zone, see how much insulation you need, and calculate your potential energy savings and federal tax credits.

How we calculate your estimate

Our insulation cost calculator combines pricing data, Department of Energy R-value recommendations, and energy savings models to give you a complete picture of your insulation project.

Material cost per square foot. Each insulation material has a distinct cost range that includes materials and professional installation. Fiberglass batts are the most affordable. Closed-cell spray foam is the most expensive but provides the highest R-value per inch.

Climate zone detection. When you enter your zip code, the calculator identifies your DOE climate zone (1 through 7) and shows the recommended R-values for attics, walls, and floors in your area. This determines how much insulation you actually need.

R-value gap analysis. Based on your current insulation level and the recommended R-value for your zone, the calculator identifies how much additional R-value you need and translates that into inches of your chosen material.

Energy savings estimate. The calculator models the relationship between R-value improvements and energy savings. The first layers of added insulation deliver the biggest savings, with diminishing returns as you add more. Savings estimates assume average U.S. heating and cooling costs.

IRA tax credit. The Inflation Reduction Act provides a 30% tax credit (up to $1,200 per year) for qualifying insulation projects. The calculator applies this automatically to show your net cost after the credit.

Regional adjustment. Your zip code also adjusts pricing for local labor rates and material costs.

For detailed insulation pricing by material, read our blown-in insulation cost guide. For R-value recommendations by climate zone, see our R-value guide.

Getting the most from your insulation investment

Start with the attic. Attic insulation delivers the biggest energy savings per dollar spent. Heat rises, making the attic the primary pathway for heat loss in winter and heat gain in summer. If your budget is limited, this is where to spend it.

Do not skip air sealing. Insulation resists conductive heat transfer, but air leaks bypass it entirely. Sealing gaps around wiring, plumbing, and ductwork penetrations before adding insulation significantly improves real-world performance.

Claim the tax credit. The IRA’s 30% credit (up to $1,200/year) can offset a meaningful portion of your project cost. This is a tax credit, not a deduction, so it directly reduces your tax bill. Keep receipts and the contractor’s invoice for your tax filing.

Choose the right material for the space. Blown-in cellulose is ideal for attic top-offs because it fills around existing batts and obstructions. Closed-cell spray foam is best for walls and tight spaces where high R-value per inch matters. Our spray foam vs. fiberglass comparison covers the trade-offs.

Check for utility rebates. Many local utilities offer $200 to $1,500 in rebates for insulation upgrades, on top of the federal tax credit. Check with your utility company or the DSIRE database for programs in your area. Our financing guide covers all available savings programs.