Use this furnace size calculator to quickly determine the appropriate furnace capacity required for your home’s heating needs.
Furnace Size Calculator
How to Use
Input the total area of your house in square feet, then select your local climate factor from the dropdown menu. Click the “Calculate” button, and the calculator will display the approximate furnace size needed in BTU/hour.
How It Works
The calculator multiplies your house area by a climate factor and an additional constant that represents the average energy (in BTU) needed to heat one square foot of your home. The climate factor adjusts the calculation based on your local climate conditions.
Limitations
The results provided by this calculator are estimates based on general assumptions and should not be used as the sole basis for making decisions. Actual furnace sizing can be influenced by many factors including but not limited to ceiling height, number of windows, insulation quality, and others. For a detailed assessment, consult with a heating specialist.