Eiruvin 8:3-4

Eiruvin 8:3

Imagine a motel with two storeys: the rooms on the lower floor open to the outside while those on the upper level open to a balcony, which has a staircase to the ground. Now imagine a courtyard where the residents live in a similar fashion, with some on the lower level and some on the upper level. If the residents of these two levels forgot to make an eiruv between them, then everything over ten handbreadths (about 30”) is considered in the domain of the upper residents and everything lower than this is in the domain of the lower residents. If the bank around a pit or a rock is ten handbreadths high, it is the domain of the upper residents; lower than this, it is the domain of the lower residents. This applies when the object is close to the upper level. If it is far away, it is considered the domain of the lower residents even if it is ten handbreadths high. The definition of “close” is within four handbreadths (about a foot) of the upper level.

Eiruvin 8:4

If a person places his courtyard’s eiruv in a watchman’s booth, a gazebo or a balcony, it is not a valid eiruv (because the eiruv must be placed in a dwelling and these structures do not qualify). One who lives in one of these structures does not impede others’ ability to carry (again, because it is not a legitimate residence regardless of whether or not someone lives there). If the eiruv is placed in a shed used to store straw or wood, a barn or a silo, it is a valid eiruv. Furthermore, one who lives in one of these structures does impede others’ ability to carry (because these structures are legally dwellings even though they were not designed for human habitation). Rabbi Yehuda says that if the home owner retains the right to use this structure, then the tenant who lives there cannot impede others’ ability to carry.