How to use the Building Heat Loss & Insulation Calculator
The Formula
BTU/hr ≈ (area × ΔT) ÷ R. Convert to watts for electric heat sizing. Add roof, windows, and infiltration separately for full models.
Practical Example
Q: Whole house? A: Sum each surface—this is one envelope segment.
About Building Heat Loss & Insulation Calculator
Heat loss formula
BTU/hr ≈ (area × ΔT) ÷ R. Convert to watts for electric heat sizing. Add roof, windows, and infiltration separately for full models.
Frequently asked questions
Q: Whole house? A: Sum each surface—this is one envelope segment.