UL listing

Definition

The certification a shop needs to build illuminated signs, which inspectors look for on the permit.

Why It Matters

An illuminated sign is an electrical product, and the label on it is what a building inspector checks. A shop without the listing subcontracts the lighted work, which is most of the value in a channel letter job, or builds it and hopes nobody asks. Ask whether the listing is current, whose name it sits under, and what share of last year's fabrication revenue was illuminated work, because losing the listing turns a manufacturer into a broker overnight and takes the margin with it.