Bava Batra 11B

אבל מייחד ליה פיתחא ⁠– אין לו אלא ארבע אמות לפני פתחו.

But if he designates an entrance leading to this pit and does not approach it from all sides, he has 4 cubits only in front of his entrance.

אמר רב הונא: אכסדרה ⁠– אין לה ארבע אמות. טעמא מאי ⁠– משום פירוק משאו; הכא ⁠– אפשר דעייל לגואי ומפרק. מתיב רב ששת: אחד שערי בתים, ואחד שערי אכסדראות ⁠– יש להן ארבע אמות! כי תניא ההיא, באכסדרה דבי רב. אכסדרה דבי רב פשיטא ⁠– אידרונא מעליא הוא! אלא באכסדרה רומייתא.

Rav Huna says: A portico [akhsadra] that opens onto a courtyard does not have the adjoining 4 cubits. The Talmud explains: What is the reason that 4 cubits were granted for each entrance? The 4 cubits were granted so that the owner would have room for unloading his animal of its burden. Here he can go inside the portico and unload. Rav Sheshet raises an objection from a baraita: Both gates of houses and gates of porticos have the adjoining 4 cubits for unloading. The Talmud answers: When that baraita is taught, it is specifically with regard to the portico of a study hall, which is closed and is not used for unloading burdens. The Talmud expresses surprise at this answer: It is obvious that this is the halakha governing the portico of a study hall, as it is a proper room. Rather, the baraita is referring to a Roman portico, which is more open than the portico of a study hall, but also not used for unloading.

תנו רבנן: בית שער, אכסדרה ומרפסת ⁠– יש להן ארבע אמות. היו חמשה בתים פתוחין למרפסת ⁠– אין להן אלא ארבע אמות בלבד. בעא מיניה רבי יוחנן מרבי ינאי: לול של תרנגולין ⁠– יש לו ארבע אמות, או אין לו ארבע אמות? אמר ליה: טעמא מאי ⁠– משום פירוק משאו; הכא ⁠– מטפס ועולה, מטפס ויורד.

A baraita states: A gatehouse, a portico, and a balcony with a staircase leading down to the courtyard have the adjoining 4 cubits for unloading. Even if 5 houses open onto the balcony, they only have 4 cubits in front of the entrance to the staircase that leads to the balcony. R' Yoḥanan asked R' Yannai: Does a chicken coop that also has a staircase have 4 cubits or does it not have 4 cubits? R' Yannai said to him: What is the reason that 4 cubits are granted? It is so that the owner will have room for unloading the burden of his animal. Here this space is not needed, as the chickens climb up to get into the coop and climb down to get out. No additional place is required for the owner to stand alongside them.