A. Placing the s'chach

1. One's intention concerning the placing of s'chach should be to provide protection from sun and heat and not just privacy [1].

However, it suffices to have in mind that one is placing s'chach on a succa for the purpose of the mitzva [2].

2. S'chach placed by a non-Jew is kosher [3]. The same applies if it is placed by a child under bar mitzva or a woman [4]. However it is preferable for an adult male Jew to place the s'chach [5] and ideally this should be the owner of the succa [6].

B. The amount of s'chach required

1. The minimum amount of s'chach required for a succa to be considered valid is indicated when slightly more than half the roof space is filled. The succa is kosher even if the lower part (ie. the living area) has equal amounts of sun and shade. But if the roof has exactly the same amount of s'chach as empty space, there will be more sunshine than shade in the lower part and this invalidates the succa [7].

2. If the s'chach covering is very thin and there are many openings in it, the succa is still kosher as long as:

a) there is no open area of three tefachim by three tefachim (24cm x 24cm) in one place without s'chach and

b) the succa has more shade than sunshine [8].

3. If in total the succa has more shade than sunshine, but there is one section of seven tefachim by seven tefachim (56cm x 56cm) which has more sunshine than shade, one should not use that area. However, the rest of the succa is valid [9].

4. The proper way to cover a succa is to make the layer of s'chach thick enough so that there is protection from winds and cold but one can still see the stars at night [10].

5. If the s'chach is thick and the stars are not visible at all, the succa is still kosher [11]. However, if the s'chach is made so thick, like the covering of a house, and no rain enters the succa even in a heavy downpour, the succa is invalid [12].

C. Kosher and non-kosher materials for s'chach.

1.Only materials which grow from the ground are kosher for s'chach [13].

Along with two further conditions:

a) the materials are detached from the ground [14] and

b) the materials still have the appearance of wood or plant. For example, ropes of flax cannot be used as their form has changed to the extent that they no longer look as if they were grown from the ground [15].

Metal and earth cannot be used for s'chach for although they come from the ground, they do not grow [16].

2. Materials that can contract ritual impurity (tuma) are not fit to be used for s'chach [17].

a) There are seven such materials: metal, wood, leather, bone, clay, woven cloth and braided animal hairs. However, these materials contract tuma only when they are formed in to a finished utensil, vessel or garment [18].

b) The halacha is that a broken vessel is no longer susceptible to tuma. Nevertheless, plain wood coming from broken articles or furniture is not kosher for s'chach since it was once susceptible to tuma [19]. Some hold that if one destroyed the furniture and the wood is no longer recognisable as having come from furniture, it is fit to be used [20].

c) Food fit for human consumption is susceptible to tuma and may not be used for s'chach [21]. A Rav should be consulted if one wishes to use branches with figs or grapes attached for s'chach [22].

3. There are several Rabbinic decrees concerning s'chach.

a) Materials that have a bad odour should not be used for s'chach [23].

b) Branches whose leaves constantly fall off are prohibited to be used for s'chach [24].

c) Bundles of wood or twigs tied together are not to be used for s'chach [25]. (There are a number of details concerning this rule. [26])

d) Boards having a width of four tefachim (32cm) are not kosher for s'chach since this size of board resembles the ceiling boards of a house [27]. (This halacha is known as gezeiras tikra.)

e) There is a custom not to use thin boards even if they are less than four tefachim [28]. Others allow their use nowadays since the reasons for the minhag no longer apply [29]. In case of necessity, they can be used [30].

f) Mats made from stalks, straw and reeds were once used by people for mattresses and under these conditions such mats could not be used for s'chach [31]. However, mats like this are used nowadays for stepping on ie. for wiping one's feet. Therefore if mats were made especially for s'chach, many poskim permit their use. However, others still prohibit using mats [32].

D. Supporting the s'chach

1. The support for the s'chach should be kosher just like the s'chach [33]. Therefore one should not support the s'chach on metal or utensils [34]. Furthermore, s'chach should not be tied with a string [35] or nailed down [36] and no utensils should be put on top of the s'chach to hold it in place [37].

2. A stone or cement wall can be used as support for s'chach [38].

3. If the support for the s'chach would otherwise be metal or something else unfit for s'chach, one should place wooden poles on top of the unfit support, preferably oriented in a different direction to the support, and use these poles to hold up the s'chach [39].

4. If a succa was already made and the support is not kosher for s'chach then b'dieved it can be used. The same holds if there is no other material available [40].

5. It is permitted to fasten the poles or frame of the succa with metal nails or to tie them with string because these fasteners only hold together the support (rather than providing direct support) for the s'chach [41]. (This principle is known as maamid d'maamid) Even though this is the minhag ha'olam, the Chazon Ish zt"l was of the opinion that one should be stringent and not use metal nails or string [42].

E. The status of a succa that is covered with invalid s'chach

Areas of non-kosher s'chach or empty spaces in the s'chach can affect the status of the succa in different ways depending on the size and location of the area [43].

1. If a succa has only three walls and the non-kosher area of s'chach is a strip four tefachim (32cm) wide running from the middle of the middle wall all the way to the end of the succa, the whole succa is passul. This is because the invalid s'chach effectively divides the succa into two parts - two succos each with two walls [44] and a succa must have three walls [45].

2. If the area of invalid s'chach measures four by four tefachim (32cm x 32cm), one is forbidden to eat or sleep under this area but the rest of the succa is kosher [46].

3. There is a halacha l'Moshe mi'Sinai called "dofen akuma". If the non-kosher s'chach is located along the sides of the succa (even all sides), this does not invalidate the succa unless it is four amos wide (1.92m). We consider it as if the adjacent wall bends over and extends all the way to the kosher s'chach. The non-kosher s'chach is thus considered part of the wall. Although the succa is kosher, one can only eat or sleep under the invalid s'chach if it is less than four tefachim (32cm) wide [47].

Practical applications of this halacha include: i) a succa built under the eaves or on a porch with some overhang that invalidates the s'chach underneath. ii) a succa which has a retractable roof that cannot close all the way leaving some s'chach permanently covered over [48]. In both cases, the covered s'chach is considered part of a bent wall.

4. If the invalid s'chach is less than four tefachim by four tefachim (32cm x 32cm), one may eat and sleep even under that area[49].

5. Empty spaces within the s'chach are different from s'chach passul. If the airspace extends from one end of the succa to the other [50], an empty area of just three tefachim (24cm) invalidates the entire succa [51]. This applies even if the airspace is adjacent to the wall because we do not apply the law of dofen akuma to an empty space [52] (see E3 above).

6. Airspace less than three tefachim by three tefachim does not invalidate the succa. However one should not eat or sleep under this area [53] if the empty space extends along the entire succa[54] or if a person's head or the majority of his body can fit under the space. If these invalidating characteristics are absent, it would be permissible to eat and sleep under the empty spaces, for there is no succa that does not have small empty spaces within the s'chach [55].

F. A succa under a tree

If a succa is located under a tree and the tree's branches prevent sunshine from entering the succa, the halacha is determined as follows:

1. If the tree prevents the majority of sunshine, the succa is passul. [56]

2. There is a difference of opinion in the situation where the tree does not prevent the majority of sunshine and most of the shade is from the s'chach of the succa itself. Unless it is a case of great need, one should not make or use such a succa even if it is directly under only a few small branches [57] and even if there is a large distance between the s'chach and the tree [58].

3. If a succa is not directly under a tree, but there are branches overhead along the side which prevent sunshine from entering the succa, it is still kosher because the branches are not directly above it [59].

1. Orach Chaim (O.C.) 635:1, Mishna Berura (M.B.) 635:1.
2. Piskei Teshuvos 635:1, Quoting Chelkas Yoav, Moadim U'zmanim, Vol.8. p.23. When one places the s'chach for the sake of the mitzva, their intention is to fulfil the mitzva properly, namely that the s'chach should offer shade. Therefore special kavana for shade is not necessary.
3. O.C., ibid: (ie: a succa of a non-Jew)
4. Ibid.
5. Chachmas Shlomo 635,Kaf HaChaim 635:8.Also based on: M.B. 649:14 quoting Magen Avraham. There are opinions that someone who is not obligated in a mitzva is not allowed to prepare this mitzva for someone who is obligated. This is only a stringency but nevertheless one should try to observe it. See also Succa K'Hilchesa p.35 note 6, who quotes Lev Chaim 2:209 who rules that s'chach placed by a non-Jew is invalid because perhaps his intention was for a permanent dwelling or for a storehouse.
A boy who is thirteen years of age but has not yet grown shtei sa'aros, (two pubic hairs), is still considered a minor. (see O.C. 55:9). If we are in doubt as to whether a thirteen year old boy has grown shtei sa'aros, the Pri Migadim, Eshel Avraham 14:1 rules that we do not have to concern ourselves if he grew shtei sa'aros. However Piskei Teshuvos 635:1 quotes HaRav Chaim Soloveitchik who ruled that the ramifications of this doubt concern obligations that are Min HaTorah, Biblical laws, and therefore one should be stringent if there is doubt that he is still a minor. Orchos Rabbeinu writes that Harav Y. Y. Kaneivsky was also stringent in this area.
6. Kaf HaChaim 625:11 following the principle: mitzva bo yoseir mib'shlucho, it is greater for one to perform a mitzva himself than through an agent. See also Kitzur Shulchan Aruch 134:1, also Piskei Teshuvos 625.3.
7. O.C. 631:1, M.B. 631:1. There are three issues to consider here. Firstly, it is not that we need more shade than sunshine. Rather, having more sunshine than shade invalidates the succa. Therefore, half shade and half sunshine is valid (Succa, 22b). Secondly, it appears to this author that the din concerning more sunshine than shade applies on the upper and lower parts of the succa. Lastly, since sunshine tends to spread out over an area, there will always be more sunshine in the lower part of the succa (Gemara ibid., O.C. ibid).
8. O.C. 631:4.See E5.For the purpose of this article we are using measurements based on the opinion of Rav Chaim Na'eh. In this instance the shiur of 1 tefach=8cm is considered the stringent opinion.
9. Rema 631:2 with M.B. 631:4.
10. O.C. 631:3, M.B. 631:5. The Mishna Berura also quotes the Pri Migadim that if one can see the stars in one area of the succa, the entire succa is valid.
11. M.B. ibid quotes Maharil and says that this is so because there are some cracks and crevices in the s'chach through which sunlight can penetrate into the succa. The Bichurei Yaakov writes that one can rely on this leniency.
12. M.B. 631.6 because it resembles the roof of a house. However if for whatever reason one cannot remove some of the s'chach, one can rely on those who rule that the succa is still valid.
13. O.C. 629:1
14. O.C. 629:13; M.B. 629:36 adds however that if it was cut and then replanted it may be used.
15. O.C. 629:4, 5, M.B. 629:12, 13.
16. M.B. 629:4.
17. O.C. 629:1.
18. Vayikra 11.32, Rambam, Kalim 1:1.
19. O.C. 629:2, 3, 6, M.B. 629: 2, 8, 10, 20.
20. Minchas Shlomo 1:22: Mikra'ei Kodesh, Succa siman 12.
21. O.C. 629:9.
22. O.C. 629:10
23. O.C. 629:14.
24. Ibid.
25. O.C. 629:15
26. O.C. 629: 15-17.
27. O.C. 629:18. The same applies even if they are turned on their side and the sides are narrower than four tefachim.
28. O.C. 629:18, M.B. 629:49. There are two reasons for this custom. (1) They might be placed in such a way as to prevent rain from entering the succa. (2) Since these boards are used as roofing for homes, it resembles a roof of a house.
29. Piskei Teshuvos 629:15 quotes Tzitz Eliezer that many Gedolim used such s'chach. Piskei Teshuvos, ibid quotes Sefer Succa Hashaleim that this was the minhag of Yerushalayim in the times of HaRav Chaim Yosef Sonnefeld zt"l, and HaRav Tzvi Pesach Frank. Their reasoning is that they do not prevent rain from entering the succa. Also it is not common to use them for roofing. It would be better if each board would not be wider than a tefach (8cm).
30. M.B. 629:50 writes that in case of emergency, it is permissible to even use boards that are four tefachim wide.
31. O.C. 629:6; M.B. 629:18, 21.
32. This is known as S'chach Netzach. See Piskei Teshuvos 629:6 who writes that the present day Poskim are in disagreement on this issue. The reasoning of those who restrict its use is that the reeds of the mats are sewn with threads of flax and have the appearance of one wide beam, which is four tefachim wide. We have already learnt that this is invalid for use as s'chach.
33. O.C. 629:7, M.B. 629:22.
34. See Section C: Materials Kosher and Not Kosher for s'chach
35. M.B. 629:26. Piskei Teshuvos 629:11 quotes B'Tzel HaChachma 5:44 that this only applies if the s'chach is very light in which even any ordinary wind can blow the s'chach away. Hence the string prevents the s'chach from blowing. However if the s'chach is very sturdy and a typical wind cannot blow it away, and one wants to tie it down just to prevent an unusually strong wind from blowing the s'chach away, then it would be permissible.
36. Magen Avraham 627:2, Sha'ar HaTzion 633:6. In this instance it is forbidden even if the s'chach can withstand an ordinary wind. Nailing the s'chach down makes the succa a permanent dwelling. See Piskei Teshuvos 629:11.
37. Rema 629:7, M.B. 629:24. Utensils would have the same status as string in note 3, and would be permissible to place on s'chach that can withstand typical winds on its own.
38. M.B. 629:22. Ma'amid, supporting the s'chach with invalid materials was restricted because one may come to use them for the s'chach itself. Since it is unlikely one would use stone as s'chach there is no concern. The Chazon Ish writes that even though some cement contains threads of metal, it is not noticeable. It is also only meant to strengthen the cement so there is no concern.
39. Mikraei Kodesh Succos 1:21. For more explanation see Piskei Teshuvos 629:7.
40. M.B. 629:22. The prohibition of using invalid materials for support is only l'chatchila, before it was built, it does not invalidate the succa. See also Biur Halacha 630, S.V. Kol Hadevarim.
41. O.C. 629:8: M.B. 629:26.
42. Chazon Ish 143:2.
43. The laws discussed in this section are discussed in O.C.632.
44. O.C. 632:1, M.B. 632:2, 14. Piskei Teshuvos 632:1 with note 10 explains that invalid s'chach can only divide the succa if its width is also at least 4 tefachim. If it is narrower, even if it extends the entire length of the succa, it is still considered one succa. See also footnote 46.
45. O.C. 630:2, M.B. 630:6. A succa which measures seven tefachim by seven tefachim is entirely invalidated by s'chach passul measuring only three tefachim by three tefachim (24cm x 24cm), O.C. 632:1.
46. O.C. 632:1. Even though when the Shulchan Aruch rules that the shiur, measurement of s'chach passul is four tefachim he is discussing a case when it extends the entire length of the succa (M.B. 632:2). The Tur, quoted in Pri Megadim, Eshel Avraham 632:4 rules that if in one area both the length and width of the invalid s'chach is four tefachim (however it is not enough to have an area which is equivalent to four square tefachim), See Piskei Teshuvos 632:1, 8. The M.B. 632:6 explains that an area which is four tefachim by four tefachim has the status of being a place for itself and cannot be battul (negated/nullified) to the rest of the succa.
47. O.C. 632:1. See M.B. 632:4, 5 for additional relevant halachos. 48. See M.B. 626:21. See Piskei Teshuvos 632:9 who offers advice for one who makes a succa on a porch in which the roof partially covers his succa.
49. O.C. 632:1. M.B. 632:3 writes that there is an opinion that one cannot eat or sleep under s'chach passul unless it measures less than three tefachim. The M.B. rules that it is preferable to follow this opinion. However the Chazon Ish was not concerned with this opinion. Shoneh Halachos 632:1, based on Chazon Ish O.C. 144:2, 4.
50. O.C. 632:2. See M.B. 632:10 for why airspace is more stringent than invalid s'chach. Though the Shulchan Aruch does not mention that the airspace must be at least three tefachim by three tefachim, we have already mentioned that when we say the Shiur for s'chach passul is four tefachim we mean four tefachim by four tefachim. The same applies to airspace, it is only invalid if it measures three tefachim by three tefachim.
51. The Rema 632:2 writes that if the airspace extends the length of the succa and there does not remain three walls and seven tefachim by seven tefachim on either side, the succa is invalid. If however there is an area with three walls and seven by seven tefachim, that particular area remains valid. See M.B. 632:13, 14 who explains the Rema.
52. Biur Halacha 632 S.V. Avir
53. O.C. 632:2. See M.B. 632:10 for the reason why airspace less than three tefachim is more stringent than s'chach passul less than four tefachim which one is permitted to eat and sleep under that area itself.
54. See Sefer Hilchos Chag B'chag 9:12 with note 20 that according to the Chazon Ish this presents a practical problem. If one uses bamboo poles for s'chach, if all bamboo is laid in one direction, ie, widthwise or lengthwise, there will be an airspace across the entire succa. Therefore one must lay at least some s'chach across. If all of the s'chach is laid out lengthwise, then some poles should be laid widthwise and would break up the airspace. Others say that a very narrow airspace even if it extends the entire length of the succa is not a problem. Some say even until the thickness of a tefach. Other shiurim are also mentioned. See Piskei Teshuvos 632:12 for more on this subject.
55. Rema, 632:2, M.B. 632:11, 12.
56. O.C. 626.1.
57. O.C. 626:1 brings two opinions on this matter. Biur Halacha S.V. V'yeish Omrim explains that the Shulchan Aruch rules according to the stricter opinion. The Pri Megadim also sides with this ruling. The Biur Halacha adds that in a time of necessity, if another succa is not available and he is unable to cut branches down. one can rely on the lenient opinion. The Rema 626:1 writes that one should not make a succa under a tree. Piskei Teshuvos 626:1 quotes Bichurei Yosef and Kaf HaChaim 626:6 who explains that the Rema's intention is that even in a case where all opinions agree that the succa is kosher, one should still not make a succa there.
58. Piskei Teshuvos 626:1 with note 4 quoting Beis Meir; Da'as Torah; Chelkas Yoav; Mikra'ei Kodesh Succa 1:15. Sefer Succa K'Hilchisa p.74 writes that he also heard the same from HaRav Shlomo Zalman Auerbach zt"l.
59. Biur Halacha 626 S.V. Tachas Ha'ilan.