About Heating Planner

Free tools for planning the heating in a UK home. Each page works out one thing and shows the formula it used. There is no sign-up.

Why Every Page Shows Its Working

Most answers to "what size radiator" or "what size boiler" are a rule of thumb with no working shown, or a sales enquiry form. Neither tells you where the number came from. Every calculator here shows its formula, a worked example you can check by hand, and the assumptions the answer rests on. The grant checker lists the rules it applies and where they come from.

These are planning tools. They do not produce a heating design, and a heat pump installation still needs a room-by-room heat loss survey by an MCS-certified installer. Every tool says so where it applies.

What every page does

Answers one question
Shows the formula it used (for the grant checker, the rules it applies)
Carries a worked example you can check by hand
States its assumptions and where the constants come from
Gives sizes in watts, with BTU alongside

How It Is Paid For

The tools are free and do not ask for any details. The site may carry advertising, and some result panels may end in a clearly labelled link to a boiler or heat pump company's own quote form. If you follow one of those links and go ahead, the site may be paid a commission. Commission never changes a calculated number.

The site does not collect your name, email or address. Any form you reach through those links belongs to the other company and falls under their privacy policy. The affiliate disclosure sets out how partner links work.

Found a mistake?

Corrections are welcome. If a number looks wrong, email hello@nomogramworks.com.

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Heating Planner

Free UK home heating tools

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