The following simplified method can be used to calculate cooling loads for residential buildings and to approximate cooling loads for some small commercial buildings if their use patterns are somewhat similar to residential occupancy. The method makes the following assumptions:
Most heat gain is through the building envelope and ventilation (or infiltration) rather than from internal sources such as lighting, people, equipment, and so forth.
The building is occupied and air-conditioned 24 hours per day.
The building consists of a single zone with no way to redistribute cooling unit capacity.
The indoor temperature can vary up to 3°F on a design day.
The thermostat setting is 75°F.
Reasonable design features will be ...