Jesus fulfilled that law and every other O.T. law. Quote me some New Covenant law please.
If you build a new house will you be sure to build a battlement on the roof to keep people from falling off? It's "the law" you know.
I had a small roof/deck over my basement exit door, about 6’ * 6’.
It was accessable from our bedroom with a door. (fire safety I guess)
The insurance folks made me put a rail around it so no one would fall off, even though it was not a ‘deck’, but an almost flat roof.