Answer
How many BTUs to heat a conservatory?
A typical conservatory needs around 8,516 BTU, but it depends entirely on the room's size and heat loss — use the calculator for your exact figure.
BTU (British Thermal Units) measures heat output. Bigger, colder or draughtier rooms need more; well-insulated rooms need less. 1 watt ≈ 3.41 BTU.
2026 figures · BTU uses standard UK heat-loss methodology; running costs use the Ofgem price cap · always confirm with a professional.