About RetrofitROI
A home-energy purchase, a heat pump, a battery, a solar system, an insulation job, usually gets its economics explained by the party selling it. A contractor's quote leads with a monthly payment. A manufacturer's page leads with a lifetime-savings claim built on assumptions it does not show you. Neither one is neutral, and neither one shows its work.
RetrofitROI exists to answer a narrower, more honest question on its own: given your actual numbers, is this specific purchase worth it, and what would have to change for a different option to win. Every tool shows the formula, the assumptions, and the breakeven point behind its answer, not just the answer itself.
Who builds this
RetrofitROI is built and maintained independently. It is not operated by a contractor, a lender, a utility, a manufacturer, or a government program, and it does not sell your contact information to any of them. There is nothing to purchase on the site itself: it stays free, fast, and static, with no account required to use any tool on it.
How accuracy is maintained
Every formula used on RetrofitROI is documented before it ships, checked against the authoritative sources listed on the sources and assumptions page, and covered by worked test cases with known-correct answers. A figure that varies by household, like a utility rate or a local incentive, is never silently assumed: it is shown as an editable planning estimate, or the tool asks you to enter your own number directly. See the methodology page for the full detail on how a result gets built.