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Manual J Load Calculator

Estimate your home's heating and cooling loads using a simplified Manual J calculation. Enter your home's construction details, insulation levels, and window information to see total BTU requirements and compare system types including furnace, heat pump, dual fuel, and geothermal options.

Manual J Load Calculator
Construction Type
Window Type
System Pricing (edit to match local rates)
Heating Load
11,103 BTU/h
0.9 tons
Cooling Load
18,123 BTU/h
1.5 tons
Lowest System Cost
$8,000.00
Furnace + AC
Envelope Losses
7,791 BTU/h
+ 3,312 BTU/h infiltration
Load Breakdown
Wall Loss
2,213
BTU/h
Ceiling Loss
1,211
BTU/h
Floor Loss
2,421
BTU/h
Window Loss
1,946
BTU/h
Infiltration
3,312
BTU/h
Internal Gains
4,800
BTU/h
System TypeCapacityInstalled Cost
Furnace + AC (80% AFUE / 16 SEER)Best value2 tons cooling$8,000.00
Heat Pump (10 HSPF / 18 SEER)2 tons$9,500.00
Dual Fuel (10 HSPF / 18 SEER + 80% AFUE backup)2 tons$11,000.00
Geothermal (COP 4.0 / 30+ EER)2 tons$22,000.00
Lowest cost: Furnace + AC at $8,000.00Based on a 2,000 sq ft wood frame home with 12 double-pane windows, the calculated heating load is 11,103 BTU/h and cooling load is 18,123 BTU/h. The furnace + ac system is the most affordable option at $8,000.00 installed.
Traditional Furnace + AC SystemThe furnace and AC combination is the most common and typically lowest upfront cost. However, operating costs may be higher than a heat pump in moderate climates. Gas furnaces are most cost-effective where natural gas prices are low relative to electricity.
This is a simplified Manual J estimate for planning purposes. A full ACCA Manual J calculation accounts for orientation, shading, duct losses, local design conditions, and more. Always have a licensed HVAC contractor perform a complete load calculation before purchasing equipment.