Home Renovation ROI Calculator

How the return is estimated

The sum itself is one line: value added is what you spend multiplied by a recovery rate for that project, and the blended figure at the top is the total value added over the total spent. Every project carries two rates, and which one is used depends on the single question about whether you are selling within five years. Selling soon: a minor kitchen recovers 78 per cent, new windows or doors 72, a bathroom 70, a finished basement 70, a loft conversion 65, landscaping 65, a new roof 60, a garage conversion 60, an extension 55, a major kitchen 54, solar 45. Staying put: those rates drop to 60, 60, 55, 55, 50, 45, 50, 50, 42 and 40 — except solar, which rises to 80, because the case for solar is the bill rather than the buyer.

Those twenty rates are our own. They sit in the region that resale surveys report and they are not read from one, they are not adjusted for your city, and the calculator has no idea what your neighbourhood pays for. Take them as a ranking of projects against each other, which is a job they do honestly, and not as a valuation. Two things the arithmetic ignores are worth naming: over-improving for the street, where a very expensive kitchen in a modest house recovers far less than any rate here suggests, and the fact that your home's value is only used as context on screen and never enters the multiplication.

The colour coding is a threshold, not a judgement about whether a job is worth doing: 70 per cent and above is green, 50 to 69 amber, below 50 red. A new roof at 60 per cent is not a bad investment — it is a repair, and a repair with no return at all still has to happen.

Every figure above was read out of the code that runs on this page. Where a number is our own judgement rather than a published one, the note says so and cites nothing. Method last checked 21 August 2026.