Many factors are involved when determining what size of an air conditioner or furnace would have the required power output to cool or heat your home. These factors include the extent of exposure to the sun and the outside air, the thickness, and type of outside wall insulation, the size of the house, type and number of windows and outside doors, the ceiling height, the age of the house construction etc. Choosing the correctly sized of air conditioner/furnace is very important to cool or warm your house properly. An air conditioner or furnace unit that’s too small won’t cool or warm your house properly, and a unit that’s too big will cost more than necessary. If you live in Southern Ontario, you may use the following charts to estimate the correct size of the heating or cooling product that you may need for your home.
Keep in mind that the following furnace output power estimates are aside from the furnace’s nominal power ratings. For example, a 95% rated efficiency furnace with a power rating of 80,000 BTU/hr has a power output of 0.95 x 80,000 BTU/hr = 76,000 BTU/hr.
Furnace Output and Air Conditioner size for a Bungalow
|
Bungalow Area [square feet] *
|
Furnace Output [BTU/hr]
|
Air Conditioner size [ton]
|
||
|
Built after year 1980
|
Built before year 1980
|
Built after year 1980
|
Built before year 1980
|
|
|
up to 1200 sq ft
|
40,000 BTU/hr
|
50,000 BTU/hr
|
1.5 ton
|
up to 2 ton
|
|
1200 to 1500 sq ft
|
50,000 BTU/hr
|
55,000 BTU/hr
|
2 ton
|
2 ton
|
|
1500 to 1800 sq ft
|
55,000 BTU/hr
|
60,000 BTU/hr
|
2 ton
|
up to 2.5 ton
|
|
1800 to 2500 sq ft
|
65,000 BTU/hr
|
70,000 BTU/hr
|
up to 2.5 ton
|
2.5 to 3 ton
|
|
2500 to 3500 sq ft
|
80,000 to 90,000 BTU/hr
|
90,000 to 100,000 BTU/hr
|
3 to 3.5 ton
|
3.5 to 4 ton
|
| * The above square footages do not include the area of the basement. | ||||
Furnace and Air Conditioner size for a semi-detached 2-storey home
|
Semi-detached House square footage *
|
Furnace Output [BTU/hr]
|
Air Conditioner size [ton]
|
||
|
Built after year 1980
|
Built before year 1980
|
Built after year 1980
|
Built before year 1980
|
|
|
up to 1500 sq ft
|
40,000 BTU/hr
|
50,000 BTU/hr
|
1.5 ton
|
up to 2 ton
|
|
1500 to 1800 sq ft
|
50,000 BTU/hr
|
55,000 BTU/hr
|
up to 2 ton
|
2 ton
|
|
1800 to 2200 sq ft
|
55,000 BTU/hr
|
60,000 BTU/hr
|
2 ton
|
up to 2.5 ton
|
|
2200 to 3000 sq ft
|
60,000 BTU/hr
|
70,000 BTU/hr
|
2.5 ton
|
2.5 to 3 ton
|
| *The above square footages do not include the area of the basement. | ||||
Furnace and Air Conditioner size for a detached 2-storey home
|
House square footage *
|
Furnace Output [BTU/hr]
|
Air Conditioner size [ton]
|
||
|
Built after year 1980
|
Built before year 1980
|
Built after year 1980
|
Built before year 1980
|
|
|
up to 1300 sq ft
|
40,000 BTU/hr
|
50,000 BTU/hr
|
1.5 ton
|
up to 2 ton
|
|
1300 to 1700 sq ft
|
45,000 BTU/hr
|
up to 55,000 BTU/hr
|
1.5 ton
|
2 ton
|
|
1700 to 2500 sq ft
|
55,000 BTU/hr
|
up to 65,000 BTU/hr
|
2 to 2.5 ton
|
2.5 ton
|
|
2500 to 3500 sq ft
|
up to 65,000 BTU/hr
|
up to 80,000 BTU/hr
|
2.5 to 3 ton
|
3 to 3.5 ton
|
|
3500 to 4500 sq ft
|
up to 80,000 BTU/hr
|
up to 100,000 BTU/hr
|
3.5 to 4 ton
|
4 to 5 ton
|
| *The above square footages do not include the area of the basement | ||||
If you are not sure about which size of HVAC unit is correct for your home, contact a trained professional that will guide you through this buying process.