Estimate cooling load from room size, sun and occupancy.
Cooling load combines the room's heat gain through walls and windows with heat from people and appliances, each converted to BTUs and summed. A room's AC needs depend on more than area, so adding occupancy, sun and appliance heat gives a load the plain area rule misses.
Cooling Load per Room
Total = (area x 15 + watts x 3.41) x sun factor + people x 500
Total = (area x 15 + watts x 3.41) x sun factor + people x 500 Cooling load combines the room's heat gain through walls and windows with heat from people and appliances, each converted to BTUs and summed.
A room's AC needs depend on more than area, so adding occupancy, sun and appliance heat gives a load the plain area rule misses.
This calculator takes 4 inputs: Room area, People typically inside, Sun exposure, Heat from appliances. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.