# The Walls-Dimensions, Number, Criteria of Validity

## 6. The dimensions of the Sukkah:

### A. The height:

Minimum height:[1] The Sukkah must have minimum height of 10 Tefachim [82 cm.[2]]. If its height is less than ten Tefach high, it is invalid. The height is measured from the floor of the Sukkah until the Sechach. Even if decorations hang within the ten Tefach space of the Sukkah, it remains valid.[3]

Maximum height:[4] The maximum permitted height that a Sukkah may have is 20 Amos [940 cm.[5]]. This applies irrelevant of the size of the Sukkah, whether it is large or small. This height is measured from the floor of the Sukkah until the Sechach.[6] This applies whether or not the walls of the Sukkah reach the Sechach. If there is more than 20 Amos between the floor and the Sechach, then it is invalid. If there is exactly twenty Amos, then it is valid. If the Sechach is above twenty Amos from the floor, but under the Sechach there is only twenty Amos of space between it and the floor [i.e. the Sechach is in the 21st Ama], then it is valid.

### B. The length/width:[7]

A Sukkah must have the minimum size of seven by seven Tefachim [57.2 x 57.2 cm[8]].[9] If it does not have this minimum size, it is invalid. There is no maximum size for the Sukkah. A round Sukkah must contain the above square dimension within its circle.[10] [The Sukkah must be at least seven Tefachim both in width and length. If it is less than seven Tefachim in either length or width, then even if it contains a total space of 7 square Tefach, it is invalid. For example, a Sukkah that is 20 Tefach by 6 Tefach is invalid.[11]]

Corner areas and rooms in a Sukkah [see illustration]:[12] A Sukkah that contains an extension area [i.e. “corner” in Halacha] that is less than 7×7 Tefachim, then that extension are is invalid, and does not join the rest of the Sukkah. [If either the length or width of the extension area is less than 7 Tefachim, it is invalid.[13] However, one may be lenient to have one’s table situated in the area of this extension, even if it is less than 7×7.[14] Likewise, rooms that are separated with Mechitzos are invalid if they contain a dimension that is less than 7×7 Tefachim.[15] Thus, not only must the entire Sukkah be 7×7 Tefachim, but any area of the Sukkah that is separate from the other areas must also contain a dimension of 7×7 Tefachim.]

 Summary: The minimum dimensions of a Sukkah is 57.2 x 57.2 centemeters with a minimum height of 82 centemeters, and a maximum height of 938 cm from the floor to the Sechach.   Q&A May one put up a Mechitza in a Sukkah?[16] A Mechitza may only be set up in a Sukkah if it leaves a dimension of 7×7 Tefachim on each side of the Mechitza, otherwise that area that contains less than 7×7 Tefachim becomes invalidated. Thus, when setting up Mechitzos in a Sukkah to separate between men and women, or to separate between diners in a restaurant or hotel, or to separate between people in quarantine, then one must make sure to leave a space of 7×7 Tefachim within each Mechitza. May one sit near the inside edge of a round Sukkah?[17] Yes. If there is furniture or appliances in the Sukkah, does it diminish from the 7×7 dimension?[18] Yes. Thus, one must beware that there remains a 7×7 Tefach free space in the Sukkah even after all the furniture and appliances are entered.

## 7. The Sukkah walls:

### A. How many walls must a Sukkah have?

The letter of the law:[19] From the letter of the law, it suffices to have two full[20] walls with a third wall using the rule of Lavud and Tzuras Pesach. This means that one is not required to have a full third wall but rather can have a partial full wall, and following the rules of Lavud and Tzuras Pesach, it is considered a full third wall. The exact details of how this Lavud wall is accomplished will be explained in D.[21]

The custom: It is a Mitzvah Min Hamuvchar to have a four walled Sukkah[22] [that does not containing any opening other than the door[23]] and so is the custom.[24] At the very least, one should try to have three complete walls.[25]

Complete walls versus walls with breaches: It is customary to make complete walls rather than walls that contain breaches.[26] If one is unable to make four complete walls then it is better to make three complete walls and have one side be open without a wall than to make four walls with breaches.[27] Nevertheless, in such a case, it is customary to make a Tzuras Pesach by the fourth wall, as explained next.

Making Tzuras Pesach by fourth wall:[28] By a three walled Sukkah, it is customary to make a Tzuras Pesach by the fourth wall for beauty purposes.

 According to the custom of building four walls, can one use the rule of Lavud for these walls?[29] According to the custom, one is to make four complete walls without resorting to the rule of Lavud. However, from the letter of the law, it suffices even if all four walls are Lavud, as will be explained in Halacha E.

### B. The criteria for a valid wall:

A wall is only considered a valid wall if the following three conditions are fulfilled:

1. Does not move with wind:[30] A wall is only defined as a wall if it is unable to move with a common wind. If a common wind can blow the wall, as is the case with sheet walls, then it is invalid. [If the wind can move it even slightly back and forth then it is invalid, even if the wind is unable to make it fall completely to the ground.[31] Some Poskim[32] interpret this to mean as follows: If the common wind can blow the sheet walls a distance of three Tefachim in a way that it invalidates the wall, then it is invalid. For example, if it can blow it three Tefachim upwards from the ground, or three Tefachim away from the Sechach, or that it creates a stomach of three Tefachim deep in a way that it does not contain ten Tefachim of wall within three Tefachim of width, then it is invalid even when the wind does not blow.]
2. Is height of 10 Tefach:[33] A wall is only defined as a wall if its height reaches ten Tefach [82 cm.[34]] from the ground. If the wall’s height reaches below ten Tefach from the ground it is invalid. If the wall reaches ten Tefach from the ground but is elevated from the ground, then if it is within three Tefach from the ground and reaches to ten Tefach from the ground, it is valid.[35] Thus ideally one can have a wall which is 7.1 Tefach tall and place it 2.9 Tefach from the ground and it is valid. Once the wall contains a ten Tefach height, it is valid even if it is a great vertical distance from the Sechach, [so long as the Sechach rests within 20 Amos from the ground].[36] It is valid even if it does not rest directly under the Sechach, but is within three Tefachim from it.[37] If, however, it is past three Tefachim from the Sechach, then it is invalid.
3. Is within three Tefach from ground:[38] The wall must be within three Tefach from the ground. Even if the wall is very high, if it is not placed within three Tefach from the ground, it is invalid.
4. Is within three horizontal Tefach from Sechach [see illustration]:[39] The wall must be within three [horizontal] Tefach of the Sechach for it to be validated as a wall for that Sechach.[40] [Se illustarion below] This however only applies if there is empty space between the wall and the Sechach. If, however, there is invalid Sechach in the area, then it is valid within 4 Amos, as explained next.
5. Dofen Akuma-Is within 4 Amos of Kosher Sechach if there is non-Kosher Sechach in between:[41] If the wall is adjacent to invalid Sechach, then if it is within 4 Amos [188. cm[42]] of the Kosher Sechach [i.e. the non-Kosher sechach takes up a space of less than 4 Amos], then the Sukkah remains Kosher as we apply the rule of Dofen Akuma. If the non-Kosher Sechach is more than 4 Amos wide and thus the wall is more than a four Ama distance from the Kosher Sechach, then the wall that is adjacent to the invalid Sechach is considered non-existent and can possibly invalidate the entire Sukkah if the Kosher Sechach will not remain with 3 Kosher walls. [The law of Dofen Akuma applies from all directions of the Sukkah, and hence it is possible to have less than 4 Amos of Sechach surrounding the Kosher Sechach from all 4 directions and the Sukkah still remain valid.[43] It is disputed amongst Poskim[44] whether the rule of Dofen Akum applies even if the wall of the Sukkah does not reach the invalid Sechach, and we thus must also apply the rule of Gud Asik. Practically, if the wall reaches within three Tefachim of the invalid Sechach then we apply the rule of Gud Asik and Dofen Akuma, and it remains valid.[45]]

How many walls must fulfill these conditions: At least two of the Sukkah walls must meet the above requirements while a third wall is to meet the requirements of Lavud, as explained in D. Any wall that does not meet the above requirements, are invalid.

 May a sliding or removable door count as one of the three Halachically required walls?[46] Yes, a door may be used as one of the three minimum required walls of a Sukkah, however the Sukkah is only Kosher when the door is closed. When the door is opened, the Sukkah is considered to have lost its wall and is considered invalid. Furthermore, at the initial time that the Secach is erected, the doors must be closed. However, once erected properly, it is permitted later on to open and close this door, even though it nullifies the Sukkah at the time of its opening. One must note that on Shabbos and Yom Tov it would remain forbidden to open and close this door, being it is invalidated when opened, and then re-validated when closed.[47] See Halacha 8!

### C. The length of the walls:

Minimum length:[48] The minimum size of a Sukkah is seven by seven Tefachim [57.2 x 57.2 cm], as explained in Halacha 6B. Thus, technically one should be required to have three walls which are each seven Tefach long. However, using the Biblical rules of Lavud, at times it suffices to have only two walls of 7 Tefach as explained in Halacha D, and at times even only one wall of 7 Tefach. This can be accomplished in the following way:[49] One has a single wall which is seven Tefach long, with another wall of 4 Tefach horizontal to it, within 3 Tefach from the end of the 7 Tefach wall. The third wall can then be made with Lavud and Tzuras Hapesach. Thus, it is possible to make a Sukkah with only one wall of seven Tefach. However, it is never possible to make two out of the three walls less than 4 Tefachim using the rules of Lavud and Tzuras Pesach.[50] Nevertheless, as stated above in Halacha A, the custom is to make three/four complete walls without resorting to the rules of Lavud.

Maximum length: There is no maximum size for the Sukkah, and hence there is no maximum size for a wall.

### D. Must the walls attach to each other and must they extend throughout the entire inside of the Sukkah, under the Sechach [see illustration]:[51]

Walls that contain breaches: A Sukkah is Kosher even if its two complete walls contain breaches which do not excel ten Amos, so long as it contains more wall space than breaches.[52]

Two walls that extend throughout the Sukkah with a third wall that does not [Illustration A]: If a Sukkah contains two full walls that extend throughout the Sukkah, and a third wall that is only seven Tefachim wide and only extends for part of the Sukkah, nonetheless, the entire Sukkah remains Kosher even without requiring Tzuras Pesach over the third wall and one of the full walls. [However, this only applies if there is not a ten Amos distance between the seven Tefach wall and the other walls, otherwise it requires a Tzuras Pesach, and according to some Poskim is invalid even with a tzuras Pesach.[53]]

Must the walls be attached by their corners-Four walls that do not extend the length of the Sukkah:[54] At least two of the walls of the Sukkah must be attached to each other, at the very least through Lavud [i.e. within three Tefachim of each other]. If none of the walls are attached, even through Lavud, then the Sukkah is invalid even if the walls are very long. [See Illustration B ]

### E. How does one make a third wall using Lavud and Tzuras Pesach?[55]

If there are two walls in an L shape:[56] If one has two walls [each of at least seven Tefach long[57] and ten Tefahc high] which are adjacent to each other in an L shape, then one is to place a plank which is slightly more than one Tefach wide[58] [more than 8.17 cm.[59], and is ten Tefach high] slightly within three Tefach [23.5 cm.[60]] from the ends of one of the walls. [Thus, through using the rule of Lavud it is considered that one has a plank of over four Tefachim, which is the majority of the length of a Kosher Sukkah.[61] According to some opinions, this requirement of a one Tefach wide pole slightly within three Tefachim of the wall is a Biblcial obligation.[62]] One is then to establish a pole of any width opposite this plank, at the end of the wall[63] and make a Tzuras Pesach for the remaining space from this pole until the plank of more than one Tefach, by placing another plank over them. [This Tzuras Pesach then makes it as if there is a full third wall of seven Tefachim.[64] This Tzuras Pesach is only Rabbinically required to validate the third wall.[65] If the opposite wall extends more than seven Tefachim, then it is only necessary to establish the pole by the seven Tefach distance mark.[66]] The Tzuras Pesach is valid even if the plank is not resting directly on the pole and the more than Tefach long plank, so long as it hovers over them. It is disputed amongst the Poskim[67] as to whether the Sechach itself can serve as the Tzuras Pesach if it hovers over the pole and plank, and the main ruling is that one can be lenient. This above ability to create a wall using the rules of Lavud for a Tefach long plank and Tzuras Pesach is only valid for one of the three walls.[68] [It is however possible to use the rule of Lavud with a four Tefach long wall and then the rule of Lavud and Tzuras Pesach for another more than Tefavch wall, as explained in C.]

If there are two parallel walls of seven Tefach:[69] If one has two walls [of at least seven Tefachim wide and ten Tefachim tall] which are parallel to each other then [it is stricter than the above case of two L shaped walls[70] and] one is to place a plank which is slightly more than 4 Tefach wide [33 cm.[71] and ten Tefach tall] within three Tefach [23.5 cm.[72]] from the end of one of the walls.[73] [Hence using Lavud one has a total of 7 Tefach, which is the length necessary for a Kosher wall.] Nonetheless, even in this case, it is disputed in Poskim[74] as to whether one must in addition also establish a Tzuras Pesach as in the previous case, by placing a pole opposite the plank at the end of the wall, and hovering a plank over it and the more than 4 Tefach plank. Practically, we rule that it is to have a Tzuras Pesach established.[75] This, however, only applies if the third wall is made using the rule of Lavud. If, however one contains a full seven Tefach wall for the third wall, then there is no need for a Tzuras Pesach to be made for the Sukkah to be Kosher.[76] [Likewise, if one contains two full walls of seven Tefachim and another two walls of more than four Tefachim, in the other directions, then there is no need to establish a Tzuras Pesach.[77] Likewise, if it is a very small Sukkah and the third four Tefach wall is within three Tefachim of both parallel walls, then it does not require a Tzuras Pesach.[78]]

### F. Making all the walls using Lavud [Placing sticks/strings within three Tefachim of each other]:[79]

Lavud of only Shesi or Eirev [horizontal or vertical bars]: It is permitted to make a four walled Sukkah using a vertical or horizontal Lavud throughout all the walls, such as to stand poles within three Tefachim of each other [i.e. Shesi/vertical Lavud], or to place strings within three Tefachim of each other for a height of ten Tefachim [i.e. Areiv/Horizontal Lavud]. However, if the Sukkah will only contain three walls, then at least two of the walls must be complete [throughout a length of seven Tefachim[80]] without resorting to Lavud, and even then, the third wall must contain a pole that is more than a Tefach wide, and establishing many narrow poles near each other using Lavud is invalid. [This means that at least two of the walls must be seven Tefachim long without the rule of Lavud, and that the third wall must contain a pole that is larger than a Tefach long. However, see Halacha C that it is possible for one of the two walls to be four Tefachim and be within three Tefachim of the full wall, thus resorting to Lavud for two out of the three walls. The above law only applies if the entire wall is depending on the Lavud, it is however permitted to make a Lavud wall even for an only three walled Sukkah as a back up wall, such as if one makes a wall using sheets then a Lavud wall may and should be used as a backup, as explained in Halacha ??.]

Lavud of Shesi and Eirev [i.e. Checkerd fence]: It is permitted to make any one of the walls using both vertical and horizontal sticks or strings, similar to a fence, and it counts as a Kosher wall even by a three wealled Sukkah.

### G. The law of a Pesel-The status of the Sechach that extends past the walls of a Sukkah:

Contains two extending walls from back wall [Illustration 1]:[81] If a Sukkah contains Sechach that extends past the back wall of the Sukkah, and the two horizontal walls likewise extend past the back wall, then if that area is at least 7x 7 Tefachim, it is Kosher so long as it provides majority shade.[82]

Contains one extending wall from back wall [Illustration 2]: If a Sukkah contains Sechach that extends past the back wall of the Sukkah, and there is one wall that extends together with the Sechach, then seemingly even if that area is 7×7, that area is not considered part of the Sukkah and it is forbidden to eat under it being it contains only one extending wall.

Contains one wall extending from open side [Illustration 3]:[83] If a Sukkah contains three walls and there is Sechach extending past the open side and one of the walls of the Sukkah extends together with the Sechach, then if that area is 7×7 that area is considered part of the Sukkah and it is permitted to eat under it even though it contains only one extending wall.

### F. The material of the walls:[84]

All materials are valid for a Sukkah [if it does not move with a common wind[85] as explained in Halacha B]. Even if the material does not lend shade to the Sukkah[86] [such as glass or transparent plastic], and hence it gives off more sun then shade, it is valid.[87] [Thus, the walls may be made even initially from material that is Halachically unfit for use as Sechach.[88]]

Material with bad odor, or material that dries and shrinks:[89] Nevertheless, one is not to use materials that give off a foul odor or which dry and shrink within the 7 days to below the minimum requirement for the wall.

Using sheets as a wall:[90] It is not proper to use sheets [whether of fabric or plastic] as material for a wall even if it is tied down well.[91] However, it is permitted to use sheets if one places poles within three Tefach of each other and hence uses Lavud to make an additional backup wall.[92] [According to all, Bedieved if one used sheets for a wall, then if they are tied down well that they do not move with the wind, the Sukkah is Kosher even if Lavud was not used.[93]]

 Practically are Sukkos with plastic walls initially valid?[94] If one places string or poles to perform Lavud to make three walls in addition to the plastic fabric walls, then even initially it is valid according to all. However, if Lavud is not being used, then one should not use such a Sukkah being it is possible that the plastic material walls will become loose and move with the wind. However, from the letter of the law, if the plastic does not move with the wind it is valid. Furthermore, some Poskim[95] rule that it is even initially permitted to use plastic sheets if they are tightly attached as it is not possible to move with the wind. How far must the sheet/plastic walls move with the wind to be considered problematic? If the wind can move it even slightly back and forth then it is invalid, even if the wind is unable to make it fall completely to the ground.[96] [Some interpret this to mean as follows:[97] If the common wind can blow the sheet walls a distance of three Tefachim in a way that it invalidates the wall, then it is invalid. For example, if it can blow it three Tefachim, upwards from the ground, or three Tefachim away from the Sechach, or that it creates a stomach of three Tefachim deep in a way that it does not contain ten Tefachim of wall within three Tefachim of width, then it is invalid even when the wind does not blow.]

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[1] Michaber 633:10; Sukkah 4b and 5b

[2] See Shiureiy Torah p. 249 that an Ama Sochekes is 49 cm., and accordingly a Tefach Sochakos is 8.17 cm [i.e. 1/48 of a cm times 8.] and by the Shiur Sukkah of 7×7 one should measure with an Ama Sochakos, and the same would apply here Lechumra. Thus, its exact Shiur is 81.7 cm; See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the ten Tefach dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1; Minchas Chinuch Mitzvah 325 who rules that by Tefachim we don’t apply the extra Dochakos or Sochakos, and this is only done by Amos

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 98.2 cm following the 9.82 measurement of Tefach Sochakos. [See Piskeiy Teshuvos ibid]

[3] See Michaber 633:9-10 and Sukkah ibid and 10b regarding if a) there are Sechach pieces and decorations that go into the ten Tefachim and b) if one dug out the floor of the Sukkah so it reach ten Tefachim.

[4] Michaber 633:1; Tana Kama in Mishneh Sukkah 2a

Other opinions in Mishneh: Rebbe Yehuda is of the opinion that a Sukkah which is higher than 20 hours is valid. [Mishneh Sukkah ibid]

Other details: Sechach is higher than 20 Amos, but it has pieces of it wwhich reach within twenty: See 633:2; Its inside contains more than than 20 Ama and hung decorations or covered floor with pillows or earth, or platform/Itztaba, which now makes it contain less: 633:3-7

[5] See Shiureiy Torah p. 249 that an Ama Dochakos is 47 cm. [as opposed to 48 for a regular Tefach], and by the Shiur Sukkah of 7×7 one should measure with the stringent approach of an Ama Sochakos, and the same would apply here Lechumra to measure the twenty Amos as Dochakos. See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the 20 Amos dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1 writes that its 938 cm accoridng to Grach Nah, taking into account the Dochakos accoridng to Chazon Ish, as he explains there in footnote 2

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 1,130 cm following the 9.42 measurement of Tefach Dochakos. [See Piskeiy Teshuvos ibid]

[6] The reason: The reason for this is because the Sechach is considered to be unable to provide shade when it is more than twenty Amos from the floor.

[7] Michaber 634:1; Sukkah 2a-3b that the Sukkah must hold the head, majority of and body and table

Does a ledge or step inside of a Sukkah count as part of the 7 by 7 required Tefachim, as is common in porches to have a ledge surrounding it,on which the fence is situated? If the ledge is less than ten Tefachim high, than it counts as part of the 7×7 required Tefachim. If more than ten Tefachim high, it is questionable if it is valid. [See Devar Shmuel 203, brought in Shaareiy Teshuvah 634:3; Bikureiy Yaakov 634:6; Gilyonei Hashas Mahariy Engel Sukkah 16b; Mikraeiy Kodesh Sukkos 1:3; Chelkas Yaakov 3:16; Orchos Rabbeinu 2:220 in name of Chazon Ish; Shevet Halevi 8:148; Hasukkah Hashaleim Miluim 5:6 in name of Rav SZ”A; Piskeiy Teshuvos 634:4]

A Sukkah made with two walls pointing diagonally [like this <]: Some say that it should be viewed as three walls, however the space in the corner which does not contain 7×7 Tefachim is invalid to sit in. [See Chazon Ish Eiruvin 72:5; Piskeiy Teshuvos 634:2]

[8] See Shiureiy Torah p. 249 that an Ama Sochekes is 49 cm., and accordingly a Tefach Sochakos is 8.17 cm [i.e. 1/48 of a cm times 8.] and by the Shiur Sukkah of 7×7 one should measure with an Ama Sochakos. Thus, its exact Shiur is 57.19 cm; See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the ten Tefach dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1; Minchas Chinuch Mitzvah 325 who rules that by Tefachim we don’t apply the extra Dochakos or Sochakos, and this is only done by Amos

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 68.74 cm following the 9.82 measurement of Tefach Sochakos. [See Piskeiy Teshuvos ibid]

[9] The reason: As only this size can hold one’s head, the majority of one’s body, and a table. [Sukkah ibid; M”B 634:1 and Shaar Hatziyon 634:1]

[10] Michaber 634:2

[11] M”A 634:1; Taz 634:1; Elya Raba ; Chacham Tzevi ; Mamar Mordechai; M”B 634:1

Other opinions: Some Poskim rule it suffices if the Sukkah contains 7 square Teafch even if there is not Seven Tefach in the width or length. [Bach 634]

[12] M”A 634:1; M”B 634:1; Biur Halacha 634:1 “Sukkah” in length; See Bigdei Yesha 634; Bikureiy Yaakov 634

Other opinions: Some Poskim negate the ruling of the M”A and rule that an extension of the Sukkah is valid just like the Sukkah itself and does not need to have its own 7×7 dimension. [Chazon Ish 144:6; Orchos Rabbeinu 2:29; See Bigdei Yesha 634; Bikureiy Yaakov 634]

The status of a Tzuras Hapesach in middle of Sukkah: If a Tzuras Hapesach is made in middle of a Sukkah, it is disputed as to whether it splits the Sukkah in two, and thus requires that both sides contain 7×7 and 3 Kosher walls for it to be Kosher. [See Minchas Yiotzchak 10:50 who rules its valid; Piskeiy Teshuvos 630:4 in name of Poskim that perhaps it is invalid]

[13] Biur Halacha 634:1 “Sukkah”, in negation of Derech HaChaim

Other opinions: Some Poskim rule that a if the length of the extension is not 7 Tefachim it is valid, so long as the width is 7 Tefachim, being that one can join the rest of the Sukkah to its legnth. [Derech HaChaim, brought in Biur Halacha ibid; Chazon Ish 144:6; Chelkas Yaakov 3:16; See Piskeiy Teshuvos 634:1]

[14] Biur Halacha 634:1 “Sukkah” in name of Bikureiy Yaakov

[15] See Q&A!

[16] So is implied from Sukkah ibid regarding the inner rooms of the Sukkah of Hilni the Queen which were made for Tzenius purposes; M”A ibid regarding a corner

[17] Biur Halacha 634:1 “Sukkah” in negation of opinion of Bikureiy Yaakov in his understanding of M”A ibid that only the actualmiddle of the circle is valid

[18] Piskeiy Teshuvos 634:1 based on ruling of M”A and Poskim ibid who invalidate an extension from a Sukkah being that in that area one does not have a 7×7 space.

[19] Michbaer 630:2; Mishneh Sukkah 2a; Tana Kama in Braisa Sukkah 6b

Other Talmudic opinions: Rebbe Shimon is of the opinion that from the letter of the law one must have three walls, and a fourth wall of a Tefach. [Braisa Sukkah 6b]

A Sukkah made with two walls pointing diagonally [like this <]: Some say that it should be viewed as three walls, however the space in the corner which does not contain 7×7 Tefachim is invalid to sit in. [See Chazon Ish Eiruvin 72:5; Piskeiy Teshuvos 634:2]

[20] See Halacha C that in truth, through the rule of Lavud, it is possible to make a Sukkah with even only one complete wall.

[21] Concept of lavud with three strings within three tefach of each other. Opinion of M”A that argues no lavud unless three walls. Opinion in Shua not to make plastic sheet sukkahs.

[22] Admur 638:2 “If he made four complete walls…without mentioning which one was made for the Mitzvah Min Hamuvchar”; Shelah Miseches Sukkah; Beis Hashoeiva; P”M 643 M”Z 4; Chayeh Adam 146:3; Alef Hamagen 626:1; Nitei Gavriel 11:1

Other Opinions: Some Poskim rule that it is a Mitzvah Min Hamuvchar to have three complete walls. [M”B 630:28] Thus according to them even initially there is no need to have four walls. Other Poskim suggest that accoridng to Kabbalah, one only have two walls and a Tefach. [Mishnas Yaakov 630 in name of Maharshak]

[23] See next regarding complete walls versus breached walls, and M”B 630:28 in name of Maharitz Geios

[24] Admur 639:10 “Today the custom is to make four walls for the Sukkah”; Sefer Haminhagim

[25] M”B 630:28 in name of Maharitz Geios; SeeRama 630:4 “Better to make three complete walls than four with breaches”

[26] Rama 630:5

[27] Rama 630:5

[28] Rama 630:3; Taz 630:4; M”B 630:19

[29] Rama ibid and M”B 630:28 that three of the walls are to be made complete without resorting to Lavu and Tzuras Pesach, and M”B ibid in name of Maharitz Geios that aside for the door, it is a Mitzvah Min Hamuvchar for the rest of the Sukkah to be completely closed up from all its directions.

[30] Michaber 630:10; M”A 630:16; Elya Raba 630:16; M”B 630:48; See also: Admur 315:3; M”A 315:3; Chavos Yair 184; Beir Heiytiv 240:19; Siddur Yaavetz Mosach Hashabbos Mitos Kesef 7 Chulya 3:8; Levushei Serud 315; Ashel Avraham Butchach Tinyana 240:11; M”B 240:25 and 30 and Biur Halacha 240:6 “Ad”; Taharas Yisrael 240:44; Kitzur SHU”A 150:6; Kaf Hachaim 240:44 and 630:65; See Piskeiy Teshuvos 240:17; Sheyikadesh Atzmo 32 footnote 11

[31] M”B 630:48

[32] Chazon Ish 77:6; Piskeiy Teshuvos 630:9

[33] See Michaber 630:9; Admur 315:3; M”A 315:3; Michaber Y.D. 282:8 regarding Sefer Torah; Rama 240:11 regarding candle; Elya Raba 240:14; Olas Tamid 240:3; Kitzur SHU”A 150:6; Kaf Hachaim 240:44; Birur Halacha 240; Piskeiy Teshuvos 240:17-18; Sheyikadesh Atzmo 32:9; Piskeiy Teshuvos 630:8

The law if there is a plank of wood resting on the short wall: See Mikraeiy Kodesh Sukkah 1:7; Chazon Ish 104:6; Piskeiy Teshuvos 630:8

[34] See Shiureiy Torah p. 249 that an Ama Sochekes is 49 cm., and accordingly a Tefach Sochakos is 8.17 cm [i.e. 1/48 of a cm times 8.] and by the Shiur Sukkah of 7×7 one should measure with an Ama Sochakos, and the same would apply here Lechumra. Thus, its exact Shiur is 81.7 cm; See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the ten Tefach dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1; Minchas Chinuch Mitzvah 325 who rules that by Tefachim we don’t apply the extra Dochakos or Sochakos, and this is only done by Amos

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 98.2 cm following the 9.82 measurement of Tefach Sochakos. [See Piskeiy Teshuvos ibid]

[35] The reason: As we apply the rule of Lavud.

[36] Michaber 630:9

[37] Michaber 630:9; See Piskeiy Teshuvos 630:8

The reason: As we apply both the rule of Gud Asik and Lavud to the Sechach. [M”B 630:43] Unlike ruling of M”B 630:31 relating to Dofen Akuma, that we do not apply both Gud Asik and Lavud. See Mikraeiy Kodesh Sukkah 1:7 and Piskeiy Teshuvos ibid footnote 45

[38] 630:9

[39] Michaber 630:9

[40] 632:2; 630:9

[41] Michaber 632:1; See Piskeiy Teshuvos 632:3-4; 635:3

May two neighbors share the same Dofen Akuma? Yes. See Piskeiy Teshuvos 632:2

What is the law if there is a space of no Sechach directly adjacent to the invalid Sechach? If it is less than 3 Tefachim, the Sukkah remains Kosher. [Shut Rav Akiva Eigar 12] This applies even if in total the wall is more than 4 Amos distanced from the Kosher Sechach. [Bikureiy Yaakov 632:10; Piskeiy Teshuvos 632:3]

What is the law if the invalid Sechach is hovering above the Sukkah [i.e. a porch is hovering above the house wall of the Sukkah and is less than 4 Amos wide]? If there is valid Sechach in that area of the Sukkah, we apply the rule of Dofen Akuma, and certainly if there is invalid Sechach there, then it applies. If, however, there is nothing there, then it is disputed amongst Poskim if in such a case we apply the rule of Chavut Rami together with Dofen Akuma. [See Ashel Avraham Butcahch 632; Eretz Tzevi 48; Sdei Chemed 2:16; Piskeiy Teshuvos 632:23]

How to build the Sukkah when relying on Dofen Akuma for a wall: In such a case one is to first build the invalid Sechach near the wall, and only then build the valid Sechach. [Piskeiy Teshuvos 635:3]

[42] See Shiureiy Torah p. 249 that an Ama is 47 Dochakos [as opposed to 48 for a regular Tefach], by the Shiur Sukkah of 7×7 one should measure with the stringent approach of an Ama Sochakos, and the same would apply here Lechumra to measure the four Amos as Dochakos. See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the 20 Amos dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1 writes that its 187.2 according to Grach Nah, when taking into account the Dochakos according to Chazon Ish, as he explains there in footnote 2

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 226 cm following the 9.42 measurement of Tefach Dochakos. [See Piskeiy Teshuvos ibid]

[43] Michaber 632:2; Sukkah 4a

[44] See M”B 632:4 for a dispute on this matter; See Sukkah 4a which implies that we apply the rule of Dofen Akuma even when the wall does not reach the Sechach as the Talmud states that one can validate 20 cubic high Sukkah by making a ledge by the side which is within 4 cubits of the wall, and this ledge obviously does not reach the Sechach. Vetzaruch Iyun

[45] M”B ibid; See Piskeiy Teshuvos 632:3

Other opinions: Some Poskim rule that it is invalid even if it reaches within three Tefachim of the invalid Sechach. [Shut Rav Akiva Eigar 12, brought in Chazon Ish 77:7]

[46] Mikraeiy Kodesh Sukkos 1:110-11; Shevet Halevi 7:56 and 8:146; Shraga Hameir 7:137; Orchos Rabbeinu 2:219; SSH”K 25 footnote 115; Piskeiy Teshuvos 630:3; 635:2; See however Kinyan Torah 3:93 who argues that the Sukkah remains Kosher even when the doors are opened; Koveitz Mibeis Levi 2:23; 3:109 and 162

[47] See Poskim ibid and Piskeiy Teshuvos 630:3

[48] See Michaber 630:2-3 regaridng the rules of Lavud; 634:1 regarding the Size of 7×7; Sukkah 3a and 15; Piskeiy Teshuvos 630:7

May one make a wall using Tzuras Pesach? See Biur Halacha 630:2 “Sheyamid” for a dispute between the Ran and Rosh if Tzuras Pesach is a Biblically valid wall for a Sukkah. Practically, it is at the evry least Rabbinically invalid.

The status of a Tzuras Hapesach in middle of Sukkah: If a Tzuras Hapesach is made in middle of a Sukkah, it is disputed as to whether it splits the Sukkah in two, and thus requires that both sides contain 7×7 and 3 Kosher walls for it to be Kosher. [See Minchas Yiotzchak 10:50 who rules its valid; Piskeiy Teshuvos 630:4 in name of Poskim that perhaps it is invalid]

[49] See Biur Halacha 630:5 “Ki” in name of Peri Megadim; Piskeiy Teshuvos 630:7; However, see M”B 630:87 that one must always have a full two walls. Vetzaruch Iyun.

Other opinions: Some Poskim rule that a Sukkah is never valid unless it has two complete walls of seven Tefachim. [Chazon Ish 75:1; See Piskeiy Teshuvos 630:1 and 7]

[50] Ateres Zekeinim 630; M”B 630:6 that the Halacha Lemoshe Misinai is that only one of the walls suffices to have a Tefach pole

[51] Rama 630:3

[52] Michaber 630:5

[53] See M”A 630:4 as explained in Machatzis Hashekel ibid; M”B 630:18 and Michaber 630:5

[54] See Rama 630:5; M”A 6390:7; Levushei Serud on M”A ibid; M”B 630:25

[55] See Michaber 630:2-3; Piskeiy Teshuvos 630:1-7

[56] Michaber 630:2; Sukkah 6a

[57] See Halacha C for scenarios in which ity is valid even if only one of the walls contains seven Tefachim

[58] See M”B 630:8 as for why it must be more than one Tefach wide, when seemingly so long as it is more than half a Tefach wide it will suffice to take up majority of the seven Tefach length.

[59] 8.16 cm is the measurement of a Tefach Sachuk, as explained in the next footnote

[60] See Shiureiy Torah p. 249 that an Ama is 47 Dochakos [as opposed to 48 for a regular Tefach], and accordingly a Tefach Dochakos is 7.83 cm [i.e. 1/48 of a cm times 8, deducted from 8 cnetimeters]  and by the Shiur Sukkah of 7×7 one should measure with the stringent approach of an Ama Sochakos, and the same would apply here Lechumra to measure the four Tefachim as Dochakos. See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the 20 Amos dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1 writes that its 31.2 according to Grach Nah, when taking into account the Dochakos according to Chazon Ish, as he explains there in footnote 2

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 37.68 cm following the 9.42 measurement of Tefach Dochakos. [See Piskeiy Teshuvos ibid]

[61] Taz 630:2; M”B 630:6; See M”B 630:8 as for why we need to have four Tefachim of a full wall, when seemingly so long as it is more than 3.5 Tefachim it will suffice to take up majority of the seven Tefach length.

[62] P”M 630 M”Z, brought in M”B 630:10; Biur Halacha 630:2 “Veyaaseh”. However, see Tosafus Sukkah 7b and P”M 630 A”A 7, who rule that it is only Rabbincially required, as Biblcially, simply placing a Tefach pole adjacent to the wall suffices. [Biur Halacha ibid]

[63] Meaning, that if the wall is seven Tefachim long, then the pole is placed by the seven Tefach mark. [M”B 630:9 in name of M”A] However, some Poskim rule thatone is to place it one Tefach over in such a case, so the Tzuras Pesach always maintain a four Tefach distnace. [M”B ibid in name of P”M in name of Hagahos Maimanis]

[64] Taz 630:2; M”B 630:6

[65] M”B 630:10; Biur Halacha 630:2 “Veyaaseh”

[66] Levushei Serud 630; P”M 631 A”A 4 in question on Levush; Shaar Hatziyon 630:2; Implication of ruling of Michbaer 631:7 regaridng a Pesel that extends past the Sukkah

Other opinions: Some Poskim rule that one must establish the pole at the very end of the opposite wall, even if it is much longer than seven Tefachim. [Levush 630, brought and negated in Shaar Hatziyon ibid; Chazon Ish 75:8; Shevet Halevi 1:169]

[67] Rama ibid rule sthat it may while the M”A 630:2 rules that it may not. The M”B 630:13 concludes like the Rama

[68] Ateres Zekeinim 630; M”B 630:6 that the Halacha Lemoshe Misinai is that only one of the walls suffices to have a Tefach pole

[69] Michaber 630:3; Sukkah 6a; Piskeiy Teshuvos 630:5

[70] M”B 630:14

[71] Four Tefachim is 32.68 using the measurement of 8.16 cm per Tefach for a Tefach Sachuk, as explained in previous footnotes throughout this book

[72] See Shiureiy Torah p. 249 that an Ama is 47 Dochakos [as opposed to 48 for a regular Tefach], and accordingly a Tefach Dochakos is 7.83 cm [i.e. 1/48 of a cm times 8, deducted from 8 cnetimeters]  and by the Shiur Sukkah of 7×7 one should measure with the stringent approach of an Ama Sochakos, and the same would apply here Lechumra to measure the four Tefachim as Dochakos. See also M”B 633:2 and Shaar Hatziyon 633:2 that by Sukkah we follow the stringent approach in the dimensions, either Dochakos or Sochakos, and by the 7×7 dimension we follow Sochakos, and the same would apply here by the 20 Amos dimension; See also Midos Vishureiy Torah pp. 48-57 regarding Ama Sochakos and Dochakos; Piskeiy Teshuvos 633:1 writes that its 31.2 according to Grach Nah, when taking into account the Dochakos according to Chazon Ish, as he explains there in footnote 2

Other opinions-Chazon Ish: According to the Chazon Ish, the measurement is 37.68 cm following the 9.42 measurement of Tefach Dochakos. [See Piskeiy Teshuvos ibid]

[73] See M”A 630:3 that perhaps this form of wall is only valid if it is within three Tefachim of the wall, and if not then it is invalid even with Tzuras Pesach, and that perhaps it must be within three Tefachim of both parallel walls. [P”M 630 A”A 4 in udnerstaiding of M”A ibid] However, see Machatzis Hashekel who claims there is an error in the M”A iobid and that it should read ten Amos, that only if the wall is a ten Amos distance from one of the walls is it invalid. Practically, the majority of Poskim negate this ruling of the M”A and conclude that it does not have to be within 3 Tefachim of both walls. [See M”B 630:15]

[74]  Michaber ibid brings two opinions; first opinion says it needs a Tzuras Pesach, second opinion says it does not

[75] M”B 630:16 in name of Bach, Elya Raba

[76] Rama ibid

[77] Piskeiy Teshuvos ibid

[78] M”A 630:3 as explained in P”M 630 A”A 3 and Machatzis Hashekel ibid

[79] M”A 630:Hakdama; M”B 630:7; Piskeiy Teshuvos 630:2

Other opinions: Some Poskim rule that Lavud only works vertically and not horizontally. [Mahrasha, brought and negated in M”A ibid] Some Poskim rule that a Sukkah wall amy never be made using Lavud of narrow sticks within three Tefach of each other. [Chazon Ish 75:12]

[80] See Chazon Ish 75:10; Piskeiy Teshuvos 630 footnote 4

[81] Michaber 631:6

[82] The reason: As in such a case that area contains all the criteria of a Kosher Sukkah, as it has three walls and is 7×7, and has majority shade. Now although the middle wall was not made for this Sukkah but rather for the main Sukkah, nevertheless it is valid to serve as a third wall also for the smaller Sukkah. [Michaber ibid]

[83] Michaber 631:7; Sukkah 19a; See Piskeiy Teshuvos 631:4

Other opinions: Some Poskim rule that the area that extends with the third wall is valid even if it is less than 7×7. [Chazon Ish 144:1, brought in Piskeiy Teshuvos 631:3

[84] Michaber 630:1

[85] Michaber 630:10

[86] Meaning that although the main aspect of a Sukkah is its ability to provide shade, of which lack thereof invalidates the Sukkah, this is only in regards to the Sechach. However, the walls are not required that they provide shade. Hence even if in the morning or evening when the sun shines at an angle towards the walls of the Sukkah there is more sun light than shade, nevertheless the Sukkah is Kosher.

[87] Michaber ibid

[88] Biur Halacha 630:1 “Kol Hadevarim” in name of Elya Raba and Birkeiy Yosef; Sefer Haminhagim p. 65

Other opinions: Some Poskim rule that the wall of the Sukkah follows the same laws as the Sechach, and hence any material that is Biblically invalid for Sechach is likewise invalid to be used as material for the walls of the Sukkah. [Darkei Moshe 630 in name of Hagahos Ashri in name of Or Zarua, brought in Bach 630 and Biur Halacha 630:1] Some Poskim conclude that it is proper to be stringent like this opinion. [Bach ibid, brought in Biur Halacha ibid; Peri Megadim in 630; Biur Halacha ibid according to Gr”a who is Machmir to invalidate an invalid Mamad, and the Chazon Ish extends this to invalidate even a Mamad Demamad]

[89] Rama ibid

[90] Michaber 630:10; Piskeiy Teshuvos 630:9

[91] The reason: Being that it is difficult to ascertain that the sheets will not move with the wind, as even if one ties them well, occasionally the ropes tear unnoticeably and he ends up having a wall that cannot stand in face of a common wind. [Michaber ibid]

[92] The reason: As in such a case even if the sheets move with the wind the wall remains Kosher due to the poles which are Lavud.

[93] Aruch Hashulchan 630:32

[94] Piskeiy Teshuvos 630:9

[95] Salmas Chaim 253; Kinyan Torah 4:70; Mishneh Halachos 5:77; Moadim Uzmanim 1:84

[96] M”B 630:48

[97] Chazon Ish 77:6; Piskeiy Teshuvos 631:9