How many BTU to heat a 3000 sq ft house?

To estimate the BTUs needed to heat a 3,000 square foot house, a common rule of thumb is to use 30-60 BTUs per square foot, depending on factors like climate, insulation, and home design. This translates to approximately 90,000 to 180,000 BTUs for the entire house. For a more precise calculation, consider conducting a Manual J load calculation that takes into account specific conditions and characteristics of the home.