MCPCalc

BTU Calculator

Calculate heating and cooling BTU load by square footage.

Scratchpad (not saved)

sq ft
ft

What This Calculator Does

Calculate heating and cooling BTU load by square footage.

It combines Square Footage, Ceiling Height, Climate Zone, Insulation Quality to estimate Heating BTU, Cooling BTU, AC Tonnage.

Formula & Method

Heating load is BTU_h = Area\cdot b_{climate}\cdot\frac{H}{8}\cdot f_{insulation}\cdot f_{sun}+1000\cdot Windows+600\cdot Occupants. Cooling load is BTU_c=0.8\cdot BTU_h and AC tons are T=\frac{BTU_c}{12000}.

Notation used in the formulas: R = Heating BTU; x_{1} = Square Footage; x_{2} = Ceiling Height; x_{3} = Climate Zone; x_{4} = Insulation Quality; x_{5} = Number of Windows; x_{6} = Sun Exposure.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

  • Square Footage: Used directly in the calculation.
  • Ceiling Height: Used directly in the calculation.
  • Climate Zone: Used directly in the calculation.
  • Insulation Quality: Used directly in the calculation.
  • Number of Windows: Used directly in the calculation.
  • Sun Exposure: Used directly in the calculation.
  • Number of Occupants: Used directly in the calculation.

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