Final answer:
The lighting demand load before derating for a house with a first floor of 1440 sq ft and a second floor of 924 sq ft, using a standard of 3 watts per square foot, is 7092 watts.
Step-by-step explanation:
The lighting demand load (before derating) for a house with outside dimensions can be calculated using the National Electrical Code (NEC) standard for lighting demand loads in residential buildings. Generally, the NEC specifies 3 watts per square foot for lighting and general electrical loads in living areas. To determine the load, we need to calculate the floor area of both the first and the second floors.
For the first floor, the area is 30 ft x 48 ft, yielding 1440 square feet. For the second floor, which has dimensions 22 ft x 42 ft, the area comes out to 924 square feet. To get the total lighting demand load, you would then add the loads from both floors.
First floor lighting load: 1440 sq ft x 3 watts/sq ft = 4320 watts.
Second floor lighting load: 924 sq ft x 3 watts/sq ft = 2772 watts.
The combined load, without further adjustments for derating or other factors, totals 7092 watts.