Calculators
Heat loss calculator
Get a rough idea of the heat pump size (kW) your home might need, from its floor area and insulation level. A sense-check, not a survey.
Rough heat-loss estimate
Figures verified July 2026
Rough heat pump size
~— kW
Why heat loss matters
Heat-loss is the amount of heat your home leaks on a cold day, and it determines the size — and cost — of the heat pump you need. This tool gives a very rough proxy from floor area and insulation. A proper MCS heat-loss survey measures every room, window, wall and door, and is the only basis for a real system size and fixed price. Use this to sanity-check a quote, then book a free survey via the main calculator.
Get a tailored estimate and a fixed quote
These tools give indicative figures. For your real numbers and the grant applied, use the full calculator or call us.