Succah 1:7-8

Succah 1:7

Regarding a ceiling of unplastered boards, Rabbi Yehuda says that Beis Shammai requires one to both loosen the boards and to remove every other board, while Beis Hillel requires one either to loosen the boards or to remove every other board. Rabbi Meir says that one must remove every other board, loosening the boards not being sufficient or necessary.

Succah 1:8

If one covers his succah with iron bars or the slats of a bed, the succah is valid so long as the space between these things is as big as the space occupied by them. If a person hollows out a haystack for use as a succah, it is no succah at all (not having been built, as is required).