Free tool · Economy → Ease → Climate fit, in that order
Climate-Zone Measure Picker
Every measure from the guide, filtered three ways. Costs are shown as bands, not prices — real prices vary too much by country to be honest at the global level. Payback ranges appear only where a verified source supports them. Everything else says "verify locally," because it's true.
How to read the money: payback periods for common investments
LED lighting under 1 year · air sealing 1–2 years · insulation 2–3 years · heat pump 4–6 years · solar PV 6–10 years. After payback, savings continue for the remaining life of the measure — often 10–20+ years. Incentives, energy prices, and local conditions can shorten these. Source: DOE Building America; NRCan. Specific values vary by location — verify locally.