Insulation & Efficiency Payback Calculator
Compare loft top-up, cavity wall insulation, draught-proofing and a smart thermostat by simple payback period, see which pays for itself fastest, and what a combined package would cost and save.
Estimate only. This is an estimate for information only, not a quote or professional advice. Get a survey and quotes from accredited installers before committing, and check current grant eligibility (ECO4/GBIS).
Choose your measures
A ranked payback table and combined package total appear here as you select measures.
How simple payback is worked out
Simple payback is how long it takes an efficiency measure's annual saving to cover its upfront install cost, install cost ÷ annual saving, in years. It's a useful, easy way to compare different measures, though it ignores things like rising energy prices (which would shorten payback over time) and the measure's full working life (draught-proofing and a loft top-up typically last well beyond their payback period, so the saving keeps coming long after the cost is covered). Cheaper, simpler measures like draught-proofing usually pay back fastest; bigger jobs like cavity wall insulation cost more upfront but often keep saving for decades.
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