How many square feet will a 60,000 BTU furnace cover?

How many square feet a 60,000 BTU furnace will cover depends on climate, insulation, and home age, but rule of thumb is 60,000 BTU input with 96 percent AFUE outputs about 57,600 BTU and can heat 1,200 to 2,000 sq ft in moderate climate, and 1,000 to 1,500 sq ft in very cold climate. BTU coverage calculation uses Manual J load that considers climate zone: in cold climate like Minnesota and Michigan requiring 50 to 60 BTU per sq ft, 60,000 BTU covers 1,000 to 1,200 sq ft, in moderate climate like Pennsylvania and Ohio requiring 40 to 50 BTU per sq ft, 60,000 BTU covers 1,200 to 1,500 sq ft, and in mild climate like Texas and Florida requiring 30 to 40 BTU per sq ft, 60,000 BTU covers 1,500 to 2,000 sq ft. For well-insulated new home built after 2010 with R-49 attic and R-20 walls, coverage is higher at 1,800 to 2,000 sq ft for 60,000 BTU. For poorly insulated old home built before 1970 with single pane windows, coverage is lower at 1,000 to 1,200 sq ft. 60,000 BTU is common size for 1,500 sq ft homes. Oversizing furnace causes short cycling, poor efficiency, and less comfort. Proper way is to have contractor perform Manual J load calculation that considers insulation, windows, air leakage, and climate, not just sq ft, to size furnace exactly.