Bava Metzia 117 - The Upper Apartment's Floor Fell In
In a case of a two-story house, the owner living on the ground floor, and a tenant in the upper story, if part of the floor of the upper apartment fell in - and the owner does not want to repair it - the occupant of the upper apartment may go down and live in the landlord's apartment below, until the landlord repairs the upper apartment for him.
What are the circumstances? If the landlord rented "this upper apartment," he would have no further obligation. If he rented "an upper apartment," he could provide another upper apartment. Our ruling is applicable when the landlord said "I am renting you this upper apartment which is on top of this lower apartment." With these words he pledged the lower apartment to support the tenancy of the upper story.