BTU Calculator — Heating & Cooling by Room

How does the btu calculator work?

Estimated BTU = room area × climate factor × insulation factor. Climate factor: 20–25 BTU/ft² for mild climates, 30 for average, 40+ for hot or cold zones. Insulation multiplier: 0.9 (well-insulated), 1.0 (average), 1.15 (poor).

What else do people ask about this calculator?

How many BTU do I need to cool a 300 sq ft room?

About 7,000–9,000 BTU for an average-insulated room in a moderate climate.

How many BTU in a ton of AC?

12,000 BTU per hour equals 1 ton of cooling capacity.

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