Base formula: 25 BTU per sq ft. Add 10% for sunny rooms, 10% for kitchens, 600 BTU per person over 2 people. 100 sq ft needs 5,000 BTU, 300 sq ft needs 7,000 BTU, 500 sq ft needs 10,000 BTU. Oversized units cycle frequently and don't dehumidify properly.
Quick Tips
- Always order 10-15% extra materials for waste
- Check local building codes before starting
- Measure twice, cut once — verify all inputs
Frequently Asked Questions
100 sf: 5,000 BTU; 200 sf: 6,000 BTU; 300 sf: 7,000 BTU; 500 sf: 10,000 BTU.
Yes, add 10% for rooms with direct sun exposure most of day.
1,000 watts equals 3,412 BTU for heating. Cooling BTU different measurement.