[Avodah] Waterproof S'chach? Really?

[Micha Berger via Avodah]

On Wed, Oct 19, 2016 at 09:58:22AM -0700, Chaim Tatel via Avodah wrote:
: Has anyone seen this in action?
: From what I've seen in the poskim, if it can't rain in your sukkah, the
: s'chah is pasul.

>From <http://www.dailyhalacha.com/m/halacha.aspx?id=2766> it seems
RYSE discusses your question, which has become a machloqes haposqim:

                         ...  Such Sechach enables one to continue
   performing the Misva of Sukka even under rainy conditions, and it
   thus might seem preferable to use such Sechach.

   Indeed, Rav Yosef Shalom Elyashiv (1910-2012), in Sefer Ha'sukka,
   ruled that it is permissible and even recommended to use this rainproof
   Sukka. He was then asked how to reconcile his ruling with the custom
   recorded by the Tur (Rabbenu Yaakob Ben Asher, 1269-1343), in the
   name of the Samak (Sefer Misvot Katan by Rabbi Yishak of Corbeil, 13th
   century), not to construct Sukkot with impenetrable Sechach. According
   to this custom, which is codified by the Shulhan Aruch, the Sechach
   must be a temporary covering which does not protect the Sukka from the
   elements. Rav Elyashiv responded that this refers to very dense Sechach
   which cannot be penetrated by wind, rain or insects, and such Sechach
   cannot be used because the Sukka must be a crude, temporary structure.
   The new rainproof Sechach, by contrast, has spaces through which wind
   and insects can enter the Sukka, but is constructed in such a way that
   rain immediately falls off the Sechach without entering the Sukka. Such
   Sechach does not violate the requirement to use a temporary covering.
   This is also the position taken by Rav Elyashiv's son-in-law, Rav
   Haim Kanievsky (contemporary), in Sheraga Meir.

   Several other Poskim, however, disagreed. The Shebet Ha'levi (Rav
   Shemuel Wosner, contemporary) wrote that we should not be trying
   to "outsmart" Halacha by devising creative strategies, and we
   should use the same kind of Sechach that Jews have been using for
   generations. Likewise, the Kinyan Ha'Torah maintained that although
   rainproof Sechach might be technically permissible, one should use the
   traditional Sechach. This is also the view of Rabbi Yishak Yaakob Weiss
   of the Eda Ha'haredit (in Keneh Ha'bosem). The Yalkut Yosef (Sukka, p.
   85) cites both views without reaching a conclusion, and it appears
   that Hacham Ovadia Yosef did not issue a ruling on this issue.

   In light of the difference of opinion that exists, it would seem that
   one should preferably not use such Sechach, especially given the fact
   that we are dealing with a Biblical obligation. However, one who
   already owns this Sechach may certainly rely on the ruling of Rav
   Elyashiv and use it for the Misva.

Tir'u baTov!
-Micha

-- 
Micha Berger             The thought of happiness that comes from outside
micha at aishdas.org        the person, brings him sadness. But realizing
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