What size heat pump do I need for 2,000 sq ft? (tons by climate zone)
A 2,000 sq ft home in climate zone 4 with average insulation needs 95,000 BTU/h of heating on the published BTU-per-square-foot rule, which is 7.92 tons: a heat pump class of 8 tons. Across the zones the same home runs from 5.42 tons in zone 1 (hot) to 9.17 tons in zone 5 (cold), so the zone matters more than anything else. The tables below give every zone and insulation level for 2,000 sq ft, the class for 1,000 to 3,000 sq ft, and the same rule in m² and kW.
Open the heat pump size calculator
1. What size heat pump for 2,000 sq ft in each climate zone?
The published rule (HVACDirect.com, How to Size Your Air Conditioner or Heater, heating factor): Zone 1 30-35, Zone 2 35-40, Zone 3 40-45, Zone 4 45-50, Zone 5 50-60 BTU per hour per sq ft, multiplied by 2,000 sq ft and by the insulation factor (poor 1.1, good 0.9). Tons = BTU/h / 12,000; the class is the midpoint rounded up to the next half ton, a rounding rule, not a product list.
| Climate zone | Range, average (BTU/h) | poor: tons (class) | average: tons (class) | good: tons (class) |
|---|---|---|---|---|
| Zone 1 | 60,000-70,000 BTU/h | 5.96 tons (6 tons) | 5.42 tons (5.5 tons) | 4.88 tons (5 tons) |
| Zone 2 | 70,000-80,000 BTU/h | 6.88 tons (7 tons) | 6.25 tons (6.5 tons) | 5.63 tons (6 tons) |
| Zone 3 | 80,000-90,000 BTU/h | 7.79 tons (8 tons) | 7.08 tons (7.5 tons) | 6.38 tons (6.5 tons) |
| Zone 4 | 90,000-100,000 BTU/h | 8.71 tons (9 tons) | 7.92 tons (8 tons) | 7.13 tons (7.5 tons) |
| Zone 5 | 100,000-120,000 BTU/h | 10.08 tons (10.5 tons) | 9.17 tons (9.5 tons) | 8.25 tons (8.5 tons) |
Zone 4 with average insulation is the calculator's starting home: 95,000 BTU/h, 27.84 kW, 8 tons. The heat pump size calculator sets the zone from your state and shows the furnace class beside the heat pump class.
2. How many tons of heat pump per square foot? (home size by zone)
The midpoint of the range with average insulation, in tons, with the half-ton class in brackets. The BTU/h figures behind these cells are in the BTU per square foot guide.
| Home (sq ft) | Zone 1 | Zone 2 | Zone 3 | Zone 4 | Zone 5 |
|---|---|---|---|---|---|
| 1,000 | 2.71 (3 tons) | 3.13 (3.5 tons) | 3.54 (4 tons) | 3.96 (4 tons) | 4.58 (5 tons) |
| 1,500 | 4.06 (4.5 tons) | 4.69 (5 tons) | 5.31 (5.5 tons) | 5.94 (6 tons) | 6.88 (7 tons) |
| 2,000 | 5.42 (5.5 tons) | 6.25 (6.5 tons) | 7.08 (7.5 tons) | 7.92 (8 tons) | 9.17 (9.5 tons) |
| 2,500 | 6.77 (7 tons) | 7.81 (8 tons) | 8.85 (9 tons) | 9.9 (10 tons) | 11.46 (11.5 tons) |
| 3,000 | 8.13 (8.5 tons) | 9.38 (9.5 tons) | 10.63 (11 tons) | 11.88 (12 tons) | 13.75 (14 tons) |
With poor insulation every cell is a tenth higher: 2,000 sq ft in zone 4 becomes 8.71 tons, a 9 tons class. Per square foot, the rule is 2.5 to 5 tons per 1,000 sq ft from the hottest to the coldest zone.
3. Heat pump size by square metre (kW)
The same rule read in m²: the area is converted to sq ft before the lookup, and kW = BTU/h / 3,412. The zones are US zones; a UK or Irish home uses the boiler size calculator and its W/m² heat loss rule instead.
| Home (m²) | Zone 1 | Zone 2 | Zone 3 | Zone 4 | Zone 5 |
|---|---|---|---|---|---|
| 100 | 10.25 kW (2.92 t) | 11.83 kW (3.36 t) | 13.41 kW (3.81 t) | 14.98 kW (4.26 t) | 17.35 kW (4.93 t) |
| 150 | 15.38 kW (4.37 t) | 17.74 kW (5.05 t) | 20.11 kW (5.72 t) | 22.48 kW (6.39 t) | 26.03 kW (7.4 t) |
| 200 | 20.50 kW (5.83 t) | 23.66 kW (6.73 t) | 26.81 kW (7.62 t) | 29.97 kW (8.52 t) | 34.70 kW (9.87 t) |
| 250 | 25.63 kW (7.29 t) | 29.57 kW (8.41 t) | 33.52 kW (9.53 t) | 37.46 kW (10.65 t) | 43.38 kW (12.33 t) |
| 300 | 30.76 kW (8.75 t) | 35.49 kW (10.09 t) | 40.22 kW (11.44 t) | 44.95 kW (12.78 t) | 52.05 kW (14.8 t) |
A 100 m² home needs 10.25 kW in zone 1 and 17.35 kW in zone 5; a 300 m² home, 30.76 kW to 52.05 kW. Rounded up to the next half ton, 100 m² in zone 3 is a 4 tons class. Rule of thumb: a Manual J calculation replaces it.
Frequently asked questions
- What size heat pump do I need for a 2,000 sq ft house?
- 90,000-100,000 BTU/h in zone 4 with average insulation, 95,000 BTU/h at the midpoint, which is 7.92 tons and rounds up to a 8 tons class (HVACDirect.com, How to Size Your Air Conditioner or Heater, heating factor). In zone 1 the same house is 5.42 tons (5.5 tons); in zone 5, 9.17 tons (9.5 tons). Table 1 has every zone and insulation level.
- What size heat pump do I need for 1,500 sq ft?
- 4.06 tons to 6.88 tons from zone 1 to zone 5 with average insulation, so a class of 4.5 tons to 7 tons; in zone 4 it is 5.94 tons, a 6 tons class. Table 2 has 1,000 to 3,000 sq ft in every zone.
- What size heat pump do I need for 2,500 sq ft?
- 6.77 tons in zone 1 up to 11.46 tons in zone 5 with average insulation, a class of 7 tons to 11.5 tons; 9.90 tons in zone 4 (10 tons). Whether a home that size gets one system or two is an installer's decision, made on the Manual J.
- How much does insulation change the heat pump size?
- By a tenth either way in the published rule: poor insulation multiplies the range by 1.1, good by 0.9 (Inch Calculator, Furnace BTU Calculator). For 2,000 sq ft in zone 4 that is 104,500 BTU/h (8.71 tons) with poor insulation against 85,500 BTU/h (7.13 tons) with good, and the class moves from 9 tons to 7.5 tons.
- Is the BTU figure the same for a furnace and a heat pump?
- Yes: the heating load describes the house, not the equipment. 95,000 BTU/h for 2,000 sq ft in zone 4 is a furnace of 100,000 BTU/h output (rounded up to the next 10,000) or a heat pump of 8 tons (rounded up to the next half ton). A heat pump also cools, so its size is checked against the cooling load as well, which the AC calculator gives room by room.
- Why does an installer size a heat pump differently?
- Because a heat pump's capacity falls as the outdoor temperature drops, an installer sizes it to the local design temperature with a Manual J load calculation that counts windows, orientation, air leakage and the building envelope, and checks the cooling load too. The BTU-per-square-foot rule here is a published shortcut for a first estimate and a check on a quote; the calculator shows it with its sources.
More guides
- How many BTU do I need for a bedroom? (12x12 and other room sizes)
A 12 x 12 bedroom is 5,000 BTU/h on the ENERGY STAR chart. Eight bedroom sizes with the sun, people and ceiling adjustments, m² to kW, and the unit class for each.
- What size boiler do I need? (UK combi and system kW by bedrooms and bathrooms)
Combi and system boiler kW for every bedrooms and bathrooms pair from the UK installers' tables, how many radiators a 24, 28 or 32 kW combi serves, and heat loss vs kW.
- How many BTU do I need per square foot? (room size chart)
The ENERGY STAR room size to BTU chart with its adjustments, heating BTU and tons by home size and climate zone, and m² to kW at three insulation levels.
Last updated 2026-09-21. Sizing estimates from published charts and rules of thumb (ENERGY STAR, manufacturer guides), each with its source and date: a Manual J load calculation by an installer is the final word.