Help Understanding Form 4562 for home office

Reviewing forms before filing, and I don't understand Form 4562 for home office.
Line 19i is showing entry for "non residential real property".
I do believe TT is taking this info from the questionnaire, but I don't understand what this form means and I want to make sure I didn't make a mistake?  Does it sound correct that I would have this form for a self-employed home office?