Furnace Size Calculator
Estimate furnace BTU/hr needed. Rule of thumb: 30-60 BTU per sq ft (regional climate dependent).
Formula
BTU/hr = Sq Ft × 30-60 (climate dependent)
2000 sqft, moderate
Inputs
- Home Size (sq ft): 2000
- Climate Zone: moderate
80,000 BTU/hr (6.7 tons)
Frequently asked questions
How to size furnace?
Consult HVAC pro; 1 ton ≈ 12,000 BTU/hr