Chicago 3 flat - WIP

First-time poster. Big time admirer! Friends, I am working on my first MOC. Long story short, I am building a Chicago block to serve as a functional plant stand. At the moment, I am enjoying the heck out of building one, the 3 flat. I have many improvements to make and I am stuck in a variety of ways. But in this instance I ask for your specific help: How should I do “fire-escapes”? These come in a variety of standards in Chicago, so I have some leeway, but I need parts help. I don't have the...