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The Dimensions and Other Requirements
The Walls:
A sukkah must have at least two full walls plus part of a third wall (the “part” needs to be a minimum of 3.2 inches wide). It is preferable, however, that the sukkah have four complete walls.
The walls must be at least 32 inches high, and the entire structure may not be taller than 30 feet. In length and breadth, a sukkah cannot be smaller than 22.4 inches by 22.4 inches. There is no size limit in how large—in length and width—a sukkah may be.