1,182. A Succah on Top of a Succah

Hilchos Shofar, Succah v’Lulav 5:21

It is appropriate for schach to be thin so that large stars can be seen through it but it is valid even if is as thick as the roof of a house and stars cannot be seen through it. If some of the schach is high and some is low, it is valid so long as there are fewer than three handbreadths (about 9”) between the upper and lower sections. If the higher schach is a handbreadth or more wide, we consider it as if it descends and touches the lower schach even if it is more than three handbreadths above it so long as the sections are aligned opposite one another.

Hilchos Shofar, Succah v’Lulav 5:22

If a person builds one succah on top of another, the bottom succah is invalid, being as if it were built inside a house. The upper succah is valid. The lower succah is invalid when the interior of the upper succah is ten handbreadths or more tall (about 30” and up) and the roof of the lower succah is strong enough to hold the pillows and coverings of the upper succah, even if just barely. If the interior of the upper succah is less than ten handbreadths tall or the roof of the lower succah is not strong enough to hold the pillows and coverings of the upper succah at all, then the lower succah is also valid. This only applies if the height of both succahs combined does not exceed 20 cubits (about 30’) because the lower succah relies upon the schach of the upper succah.