Old part of the house will be turned into a library. I've removed the bedroom at the top of the stairs, so I need to create a rail on the landing. I'd like to use a bookcase as the rail to meet the code.

How to best secure the bookcases? Any suggestions on build/design?

I was thinking of building a large 2x frame, securing it to the floor, and covering it with birch plywood and some finish molding.