What demand factor is applied to any excess general lighting and small appliance load over 120,000VA in multi-family dwellings?

In the context of load calculations for multi-family dwellings, the demand factor applied to any excess general lighting and small appliance load over 120,000 VA is 25%. This demand factor is established in the National Electrical Code (NEC) and considers that not all connected lighting and small appliance loads will be used at their full capacity simultaneously.

When calculating the loads in multi-family residential buildings, it's important to account for diversity, which means recognizing that while many devices may be installed, they won’t all be operating at the same time. The application of a 25% demand factor for loads exceeding 120,000 VA allows for a more accurate and practical assessment of the actual load that will be drawn during peak usage times, ensuring that the electrical system is neither overbuilt nor underprepared for the demands placed upon it.

This consideration is crucial for the design of electrical systems to maintain safety and efficiency, allowing for proper sizing of feeders and services in multi-family residential applications.