How big of a generator do I need to run a 2000 sq ft house?

A 2000 square foot house typically needs 10 to 14 kW of generator to cover essentials: refrigeration, well pump or sump, furnace fan, lights, and receptacles.

Running the whole house without load management, central air included, pushes the number to 18 to 24 kW. Air conditioning is the deciding load; its starting surge is several times its running draw.

Square footage is only a proxy. The honest answer comes from listing the loads you refuse to lose and adding their starting requirements, which is a small version of an NEC load calculation.

A 10 kW unit with a smart load-shedding transfer switch often outperforms a bigger generator sized by guesswork.

The home generator wattage calculator builds that list for you and totals the surge correctly.