How many BTU for 1,000 sq ft?

In a hot climate with 8 ft ceilings: about 113,267 BTU/h shaded, or 135,921 BTU/h with direct sun. In a mild climate the 20–25 BTU/sq ft rule gives 20,000–25,000 BTU/h — use that as the floor for insulated rooms.

How many tons is that?

113,267 BTU/h equals 9.4 tons of cooling (1 ton = 12,000 BTU/h) — about 33.2 kW.

Cooling · Room sizing

What size AC for a 1,000 sq ft room?

A 1,000 sq ft room with 8 ft ceilings needs about 113,267 BTU/h (9.4 tons) of cooling in a hot climate — buy a 60,000 BTU unit, or 60,000 BTU if the room gets direct sun.

By ceiling height

Ceiling	BTU/h (shaded)	BTU/h (sunny)	Tons
8 ft	113,267	135,921	9.4
9 ft	127,426	152,911	10.6
10 ft	141,584	169,901	11.8

Hot-climate volumetric method (500–600 BTU/h per m³) — the same formula as our BTU calculator, where you can enter exact dimensions. In mild climates use the room-size chart's 20–25 BTU/sq ft column instead.

FAQ

How many BTU for 1,000 sq ft?: In a hot climate with 8 ft ceilings: about 113,267 BTU/h shaded, or 135,921 BTU/h with direct sun. In a mild climate the 20–25 BTU/sq ft rule gives 20,000–25,000 BTU/h — use that as the floor for insulated rooms.
How many tons is that?: 113,267 BTU/h equals 9.4 tons of cooling (1 ton = 12,000 BTU/h) — about 33.2 kW.

Other sizes: 800 sq ft · 1,200 sq ft · any size