RetrofitROI

Is this home-energy purchase actually worth it?

A heat pump, a battery, a tankless water heater, a solar system, a Level 2 charger: every one of these decisions gets buried in a contractor quote, a marketing page, or a one-number calculator that never shows its assumptions. RetrofitROI is a free, browser-side set of decision tools that turns each of those purchases into a transparent economic model: what it actually costs after financing, what it saves, when it pays for itself, and what would have to change for a different option to win instead.

RetrofitROI turns "should I buy this?" into a transparent, editable economic model: payback period, financing comparison, breakeven conditions, and the next question a homeowner did not know to ask.

What RetrofitROI actually decides

Every tool on RetrofitROI answers one question: is this specific home-energy purchase worth it, and which option wins, given the numbers you actually have. That covers eight connected decision areas, spanning the purchases that come up when a system ages out, a utility bill changes, or a homeowner is weighing whether to convert a gas appliance to electric.

Not sure where to start? The resources library explains the ideas shared across every cluster, like payback versus NPV, reading a utility bill, and financing versus discount rates, before you dive into a specific engine.

What RetrofitROI is not

RetrofitROI is not a contractor lead-generation funnel, a live-quote service, or a product marketplace. It does not collect your contact information to sell to an installer, and it never adjusts a recommendation to favor a lender, a manufacturer, or an advertiser. It is also not a sizing or code-compliance tool: it will not tell you what wire gauge, breaker size, or BTU load a job requires. That is deliberately out of scope, because it is a different kind of question than the one RetrofitROI answers. If you need installation-grade sizing math, that work belongs with a licensed contractor or a dedicated trade-focused tool, not a homeowner economics site.

RetrofitROI answers "is this worth buying, and which option wins." It does not answer "what size or gauge does code require." Those are different jobs for different tools.

How the numbers stay honest

Every calculation runs in your browser, using deterministic finance math: simple and discounted payback, amortized financing comparisons, and explicit breakeven solving, never a black-box estimate. Where a figure depends on something that changes, like a utility rate or an incentive, RetrofitROI asks you for it directly and shows an editable planning default with its source, instead of quietly assuming a number on your behalf. See the methodology page for exactly how a result is built, and the sources and assumptions page for where every default comes from.

A value you enter for one tool, such as your electricity rate or your home's climate zone, carries into other tools that use the same value, so you are not asked to retype it. Nothing you enter leaves your browser. See the privacy page for the full detail.