When can a building use the Washington state energy code in lieu of NEC 220.12 for lighting load calculations?

A building can use the Washington State Energy Code in lieu of NEC 220.12 for lighting load calculations when its design complies with the state code. This is because the state energy code outlines specific requirements and methodologies for calculating energy efficiencies and loads that may differ from those provided in the National Electrical Code (NEC).

When a building's design aligns with the standards set forth in the Washington State Energy Code, it indicates that the building not only meets the safety and performance requirements but also adheres to energy efficiency measures. This compliance allows for a streamlined approach to energy calculations, accommodating any specific provisions the state code might have over the NEC.

The other options do not hold as they either suggest conditions that are too general—like merely having inspections and approvals—or apply limitations like exclusivity to commercial buildings, which does not reflect the broader applicability of the state energy code. Additionally, exceeding a certain square footage does not automatically qualify for this alternative calculation method, as compliance with the design regulations is what fundamentally determines eligibility.