Powder coating is one of the commonest finishes for steel products destined for outdoors or long service: it offers durable protection and a wide choice of colours, but it involves a process whose time and cost should always be costed separately from production.
The process in brief
The piece is first cleaned and treated so the coating adheres, then the powder is applied electrostatically, and finally the piece goes into an oven to cure at a controlled temperature. Each of those steps takes time and, often, means sending the work to a specialist supplier.
Lead times to allow for
If coating is subcontracted, the piece leaves the shop and comes back only after the full treatment cycle — a period that must be added to production time when planning the customer's delivery, not hidden inside a vague safety margin.
How to put it on the quote
Coating should always be a separate cost line, with its own price per square metre or per piece, and its own stated lead time. Blending it into the production cost makes it impossible to see later which part of the final price came from the structure and which from the finish.