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What size heat pump for a 1930s semi?

A 1930s semi typically needs a 8–11 kW air-source heat pump. Cavity walls; a strong candidate once loft and cavity insulation are done.

Older, solid-wall homes lose more heat, so insulation and correctly-sized radiators matter as much as the heat pump itself.

Estimated size8–11 kW
First stepInsulation + heat-loss survey

Are heat pumps good for old houses? →

2026 figures, based on Energy Saving Trust, Ofgem & gov.uk data · always confirm with a professional survey.

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