What size furnace do I need?

As a rough guide, multiply square footage by 30–60 BTU depending on climate. A 1,800 sq ft home in a cold climate needs roughly 90,000 BTU.

Is bigger always better for a furnace?

No. An oversized furnace short-cycles, wastes energy, and wears out faster. Proper sizing matters more than maximum output.

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What size furnace do I need?: As a rough guide, multiply square footage by 30–60 BTU depending on climate. A 1,800 sq ft home in a cold climate needs roughly 90,000 BTU.
Is bigger always better for a furnace?: No. An oversized furnace short-cycles, wastes energy, and wears out faster. Proper sizing matters more than maximum output.