MB4 199a: Rooftops and Ledges on Shabbos (345:15-18)

Is a a rooftop that extends beyond the walls of a house a private domain or a karmelit (do we say גוד אסיק)?

The status of holes in the wall of a karmelit.

A karmelit must be 4x4 tefachim and only extends up to 10 tefachim, the area above ten tefachim is a מקום פטור.