Eiruvin 9:2-3

Eiruvin 9:2

If a large roof adjoins a small roof, one may bring vessels from the house to the large one but not to the small. If a large courtyard has a breach into an adjoining small courtyard, residents may carry in the large one but not in the small because the breach (which is an entire wall missing from the perspective of the smaller courtyard) is like a doorway to the larger courtyard. If a courtyard has a breach that opens to the public domain, one who carries between the courtyard and the private domain is liable according to Rabbi Eliezer (who considers the breached courtyard like a public domain). The Sages say that one who carries between the courtyard and the public domain is exempt because the breached courtyard is like a karmelis.

Eiruvin 9:3

If, on Shabbos, a courtyard becomes breached to a public domain on the corner (so that it is breached on two sides), it may be carried in for the remainder of that Shabbos but it may not be carried in on subsequent Shabboses; the same is true of houses that are breached on two sides and alleys whose horizontal or vertical beams have been removed. This is the opinion of Rabbi Yehuda; Rabbi Yosi says that if these places are permitted that Shabbos, they are permitted on subsequent Shabboses, and if they are prohibited on subsequent Shabboses, they are prohibited on that Shabbos.