Insulation Calculator

Calculate insulation costs, energy savings, and payback period for a project you've already sized -- enter your own expected energy savings percentage.

This calculator turns an insulation project into a cost, an annual energy savings figure, and a payback period, given the area to insulate, its cost, current heating cost, and an expected percentage energy savings. R-Value is collected as an input, but it never actually enters the Total Insulation Cost, Annual Energy Savings, or Payback Period formulas -- the calculator relies entirely on the Energy Savings percentage you enter to represent how effective the insulation will be, so R-Value is informational context rather than a driver of the math. Area to Insulate and Cost Per Square Foot both scale Total Insulation Cost directly and proportionally. Energy Savings drives Annual Energy Savings directly -- it's applied as a straight percentage of your current Annual Heating Cost -- and because Payback Period is Total Cost divided by Annual Savings, a higher Energy Savings percentage both increases the savings and shortens how long the investment takes to pay for itself. If you're comparing insulation with different R-values, you'll need to estimate the Energy Savings percentage each one would realistically deliver yourself, since the calculator won't derive that percentage from R-Value automatically.