The OP has an uncompensated work issue, not a copyright issue. It really doesn’t matter if the railing is ever constructed.
Jason, are you sure about the first paragraph you wrote ?
If I buy a book, I can copy the pages for making my notes on. What I cannot do is copy the book and sell/handout the copies for others to avoid the purchase of said book.
Works for plans too. There should be no legal issues with a client making copies of plans to hand off to various contractors for bidding purposes if the client has compensated me for that design.
However, if that client owns two properties that are very similar, they cannot legally contract(buy) for plans for one property, and then reuse those same plans without compensation. This could be applied to work within a single property.
Similarly, if a contractor receives a set of plans for bidding purposes, they cannot perform work according to those plans on another project (compensated or not).
asking for compensation for every bid set seems a bit too much.
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