What size air conditioner for 1100 sq ft? BTU answer and adjustments
The 1100 sq ft answer: 22,000 BTU/h baseline (= 1.83 tons = 6.4 kW), 24,200 with strong sun, 19,800 in shade, 26,000 for a kitchen, 23,200 with four regular occupants. The formula is transparent — floor area × 20, then the ENERGY STAR adjustments.
| Scenario | Rule | BTU/h |
|---|---|---|
| Baseline room | 1100 × 20 | 22,000 |
| Very sunny | +10% | 24,200 |
| Heavily shaded | −10% | 19,800 |
| Kitchen | +4,000 | 26,000 |
| Four regular occupants | +600 × 2 | 23,200 |
Conversions: 12,000 BTU/h = 1 ton = 3.517 kW. 22,000 BTU/h ≈ 1.83 tons ≈ 6.4 kW. Figures are cooling capacity to look for on the spec sheet, not electrical input.
Which unit, in practice
For 1100 sq ft, shop for an 18,000–24,000 BTU mini-split, or central/ducted equipment for enclosed layouts. If you land between sizes in a humid climate, choose the smaller inverter model — longer cycles remove more moisture, and moisture is most of the discomfort.
See the full sizing guide, then choose between a window AC, a ductless mini-split or — last resort — a portable. Indian readers: tonnage rules for India.
Frequently asked questions
How many BTU for 1100 square feet?
22,000 BTU/h as a baseline (20 BTU/sq ft), 24,200 for a very sunny room, 19,800 for a shaded one, plus 4,000 for a kitchen and 600 per occupant beyond two. That is about 1.83 tons or 6.4 kW.
What size AC unit is that?
An 18,000–24,000 BTU mini-split, or central/ducted equipment for enclosed layouts. For whole-house systems serving several enclosed rooms, a Manual J load calculation replaces this room-level rule.
Is 20 BTU per square foot always right?
It is the room-unit baseline ENERGY STAR and the DOE use; ceiling height above 8 ft, poor insulation and big west glazing push it higher, while a well-insulated shaded room can sit lower. The adjustments above capture the common cases.