Privacy

This worksheet calculates results in your browser. Your selected project, ZIP code, state, quote amounts, and answers are saved in this browser's local storage so you can return later. Quote amounts and answers are not sent to our server by the worksheet. Use “Clear this case” on the main page to remove the saved case from this device.

If you enter a five-digit ZIP code, the site sends that ZIP code to our server, which uses the Zippopotam.us postal lookup to find a city and state. For heating and cooling projects, the server also uses the ZIP center coordinates to request a nearby climate station and its 1991–2020 climate normals from NOAA. NOAA receives a geographic search area, not your quote amounts. No quote amounts are sent with either lookup. You can skip ZIP lookup and choose your state manually. The electricity reference comes from an EIA state-level data snapshot, not a lookup of your address or utility account.

The site currently does not ask for your name, address, email, documents, or account. It does not currently load advertising or analytics scripts. Ordinary hosting infrastructure may still receive the technical request data needed to serve pages, such as IP address and browser details.

If advertising, analytics, or uploads are introduced later, this page and any required consent controls must be updated before those features go live.

Updated September 2026.