Does a load calculation need a PE stamp in California?

The statute

In California, anyone who practices or offers to practice electrical engineering must be licensed by the Board for Professional Engineers, Land Surveyors, and Geologists. Practice-act licensing means the work itself is restricted, and not only the use of the title. Preparing engineering for a permit is practising.

A licensed contractor may design electrical systems, in accordance with the applicable codes, for work it will install and supervise itself within its licence classification. The section does not allow a contractor to design work that somebody else will install. That is the whole of the exemption. A contractor upgrading a service it will install may calculate the load for it. A contractor may not prepare the calculation for work another contractor will install, and nothing in the section overrides an authority that requires a seal.

The authority

Whether a permit application needs a sealed calculation is decided by the authority having jurisdiction, inside what the statute allows, and it differs between California cities. LADBS's electrical permit guidance requires electrical plans to be filed for plan check where an installation's total load exceeds 400 amperes or equipment is rated 600 amperes or more, and it publishes its own NEC Standard Electrical Load Calculation form. Whether the plans and the calculation on a given project have to be prepared by an engineer is LADBS's call on that project, so ask before submitting.

Elsewhere in the state the threshold and the practice differ. The reliable answer for any California authority is the one it gives you before the submittal, and the reliable way to avoid a returned application is to have the calculation sealed where there is any doubt.

The code

NEC 220.87 defines the method for establishing an existing load from measured demand and says nothing about who signs the result. The stamp question is a licensing and permitting question, never a code question, which is why the answer changes at the state line and again at the city line.

Who seals a Wattif study in California

A Professional Engineer licensed in California, sealing under their own licence and their own insurance, whose name, licence number and jurisdiction appear on the document. Wattif holds no engineering licence and seals nothing. The report says separately that the measurement and the drafting are ours.