What size boiler for a 4-bed house?

A 4-bedroom home usually needs a 30–35 kW combi boiler (or a system boiler with a cylinder if you have two or more bathrooms).

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Answer

What size boiler for a 4-bedroom house?

A 4-bedroom home usually needs a 30–35 kW combi boiler (or a system boiler with a cylinder if you have two or more bathrooms).

Combi size	30–35 kW
2+ bathrooms	Consider a system boiler + cylinder

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

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