Heat Output & Radiator Sizing Calculator

Estimate the required heating output for your room based on British Standards.

1. Room Details

Room Type

Number of Radiators in Room

Room Dimensions (L x W x H in Metres)

Number of External Walls

Wall Construction

Window Type

Total Window Area (m²)

Floor Situation

Ceiling Situation

Total Heat Requirement

-- Watts

-- BTU/hr

Room Volume -- m³

Internal Target --°C

Recommended Radiator

Calculating...

Based on 600mm height at ΔT 50°C

Cross-sections (Top View):

Add 15% Safety Margin

Highly recommended for UK winters to account for extreme cold spikes.

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