Insulation / draught-proofing payback checker

Enter your own quote (cost) and your own estimated annual saving for each fix. The checker ranks them by payback — shortest first — and shows the 5-year net. It never invents a cost or a saving: if you do not know the saving, use the bill audit first, or get an assessor's estimate.

Estimate — verify on your bill and get a real quote before spending. Check grants before you spend: a grant changes the payback.

Insulation: what pays back first · Grants: check before you spend

Fix	Cost (your quote)	Est. saving / year