Dear Reb Naftoli,

(a) The simple answer is that he doesn't have to raise the Sechach. The clearest proof of this is the Gemara (Sukah 8b) and Shulchan Aruch (635:1) that tell us that the Sukah of a non-Jew is Kosher. This is referred to as Sukas Ganbach (see Shulchan Aruch there for an explanation of this term). The Shulchan Aruch explains that a Sukah does not have to be built with the intent of using it for a Mitzvah (l'Shem Mitzvah). It only needs to be built with the intent of providing shade (l'Shem Tzel). It is not like Tzitzis which need to be made l'Shem Mitzvah (it is also not like a Shofar that does not require any Kavanah at all). As long as it is clear to us that the non-Jew did not built it simply to provide privacy then it is okay.

(b) The more complicated answer is that it seems to be a Machlokes Rishonim.

The Gemara in Menachos (42b) tells us a rule that only someone that is commanded to wear Tefilin can write the parchments for the Tefilin. Rabeinu Tam in Gitin (45b) derives a general principle from this rule that if a person is not commanded to do a certain Mitzvah then he cannot fashion the object needed to do that Mitzvah. Therefore, Rabeinu Tam himself says that a woman cannot tie together the four species of the Lulav (the Eged) and she cannot tie Tzitzis on to a Talis. He doesn't mention building a Sukah, but Tosfos understands that his principle would apply to a Sukah as well. Accordingly, if a non-Jew builds a Sukah for a Jew, the Jew will have to place the Sechach down and if the non-Jew laid it down, the Jew will have to pick it up and put it down again.

Even though the Magen Avraham (14) seems to accept the opinion of Rabeinu Tam, at least l'Chatchilah, the Mishnah Berurah (14, Bi'ur Halachah, D"H l'Hatzrich) seems to completely reject it. His final Psak, though, is to defer to the Pri Megadim (on this Magen Avraham) who says to be Choshesh for the opinion of Rabeinu Tam l'Chatchilah. (The Halachic discussion referenced here deals with the question of women tying Tzitzis. Presumably the same Psak Halachah applies to the question of non-Jews building a Sukah).

What does Rabeinu Tam do with the Gemara in Sukah that says explicitly that a non-Jew's Sukah is kosher? This is a difficult question. The Pri Megadim (ibid) tries to answer the question but ends with Tzarich Iyun.

Kol Tuv,

Yonasan Sigler

This is not a Psak Halachah