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Home Radiator BTU Calculator

Find the ideal radiator size for your room using simple choices — no technical knowledge required!

1. Room Dimensions

metres
metres
metres

2. Your Region in the UK

Your location affects outdoor temperature calculations

3. Wall Information

External walls that face outside
Type of construction material used

4. Windows

Type of glazing installed in your windows

5. Additional Factors

Floor level of the room
How draughty is your room?

Your Estimated Heating Requirement

BTU Range
0
BTU/hr
Watts Range
0
Watts
✅ Our Recommendation: We recommend choosing radiator(s) with a combined output towards the upper end of this range for maximum comfort on colder days. It's always better to have slightly more heating capacity and adjust the temperature down, rather than struggling to heat your room adequately.
⚠️ Important Notice

This calculator provides estimated values based on typical UK conditions using professional heat loss calculation methods. The ±15% comfort range reflects real-world variations in insulation, draughts, and heat retention.

For accurate heat loss calculations, professional system design, or installations requiring Building Regulations compliance, please consult a qualified heating engineer who can perform detailed calculations following CIBSE standards and UK Building Regulations Part L.

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