Brain Tease: Commercial Lighting

[jar546]

A library installs can lights for "mood" lighting with new luminaires that contain incandescent bulbs so they can dim them. The install is in the magazine/newspaper room which is 38' x 38'. Each new can is labelled max wattage 100. Their plan is to install 20 new recessed can lights with 75watt bulbs. Does this meet the energy code assuming it is the IECC?

This will be the only lighting in this room.

 

[Mac]

No, not in NY State. the current energy code sec. 505.5.2 "Interior Lighting Power" refers to a use chart, which for libraries, calls for 1.3 times the square footage of the room in lighting wattage. In the example, the adjusted room size is 1877 sq. ft., with only 1500 watts provided.

Using 100W bulbs would work.... or a combination of wattages totaling more than 1877.

Net question please.

 

[jar546]

The actual size(rating) of the screw in lamp type incandescent for these cans is actually not relevant. The wattage must be determined by the rating of the luminaire, which in this case is 100W. 20 luminaires x 100W = 2000 watts which exceeds the 1.3 watts per square foot.