Guidelines to Kosher "S'chach"
In order for the "s'chach" (roofing) of a sukkah to be halachically acceptable it must fulfill three basic conditions. The first condition is that the material from which the "s'chach" is made be earth-grown, from the plant kingdom, like branches or bushes. Metal, lead, and plastic, although they originate from the earth, are unacceptable for "s'chach" because they are non-living.
The second condition is that this earth-grown substance be detached from its source; so long as the branches are still attached to the ground, they are not acceptable for "s'chach". Therefore, it is forbidden to build a sukkah under a tree, using the tree's branches as "s'chach".
The third condition is that the "s'chach" not be made from anything that can receive impurity; generally speaking, containers, clothing, chairs, and beds are the objects capable of receiving impurity. As a rule, any natural product that in its unaffected form cannot receive impurity becomes capable of receiving impurity after it has been manipulated and made acceptable for the use of man; with its elevation to the status of a significant utensil it becomes suited for receiving impurity. From this point onward, should it come into contact with a corpse or any other object that causes impurity, the utensil becomes impure. From the moment that the wood becomes capable of receiving impurity, it becomes unacceptable for "s'chach".
Therefore, it is permissible to roof a sukkah with branches, bushes, or even simple boards like those used for construction, because they are not capable of receiving impurity. However, if the wood was at one time used as part of a chair, bed, or container, it is forbidden to roof a sukkah with it. The Sages even forbade using the pieces of a broken container or bed for "s'chach", despite the fact that they are no longer capable of receiving impurity, lest someone make the mistake of using them for "s'chach" while they are still whole. (Shulchan Arukh, Orach Chaim 629:1,2).
The Sages also forbade building a sukkah from foul-smelling materials, or roofing with "s'chach" from which leaves or worms fall, lest due to the foul smell or the falling leaves one leave the sukkah and go into his house. Yet, if one already roofed with these sorts of branches one is not obligated to replace them. Still, if the stench in the sukkah is so strong that people are unable to bear it, the sukkah becomes invalidated in the eyes of the Torah, for it is not fitting for human habitation. (ibid. 629,14; Mishna Berurah 38).
More Sun than Shade
The "s'chach" must act as a shield against the sun. Therefore, so long as it keeps out most of the sunlight it is kosher, for we follow the majority. Yet, if even half of the sun's rays manage to penetrate the "s'chach", the sukkah is rendered invalid. This is gauged by looking at the"s'chach" itself as opposed to the floor of the sukkah. This is because the sun's rays widen as they pass through the holes in the "s'chach" and descend to the earth, and it sometimes appears that there is more sunlight in the sukkah than there is shade. All the same, if an examination of the "s'chach" itself shows that the shade is greater than the sunlight, the succah is kosher.
If under a small portion of the "s'chach" there is more sunlight than shade, the entire sukkah as a whole remains kosher. In such a situation, even those who sit under the weak "s'chach" where there is more sunlight than shade, fulfill the mitzvah of dwelling in a sukkah. One must make sure, though, that nowhere in the "s'chach" is there an area that occupies seven square handbreadths (56 cm x 56 cm) in which the sunlight is greater than the shade. If this is the case then this area of the sukkah is invalid.
Occasionally the "s'chach" is not arranged evenly, such that for part of the day there is more shade than sunlight, while during the rest of the day the amount of sunlight in the sukkah exceeds that of the shade. In such a situation, Jewish law says that the sukkah is judged according to the situation at noontime, when the sun is in the middle of the sky. If at that time the amount of shade in the sukkah is greater than the amount of sun, it is kosher; if not, it is not kosher (Rema, 631:5).
Some Laws concerning "S'chach"
If in the kosher "s'chach" there is an opening that possesses a width of three handbreadths (24 cm.), it is seen as causing a break in the "s'chach" and may quite possibly invalidate the sukkah. This is because such an opening causes the sukkah to be seen as not having three walls. If the opening's width is less than three handbreadths, yet contains enough room for the head or most of a person's body, it does not disqualify the sukkah, yet one who sits under it has not fulfilled the obligation to dwell in the sukkah. If the space is even smaller than this, it is as if nonexistent; therefore, one who sits under it fulfills the mitzvah of dwelling in the sukkah (Shulchan Arukh 632:2).
It is best to roof a sukkah such that there is abundant shade inside. All the same, there should not be too much "s'chach"; there should not be so much "s'chach" that it becomes impossible to see the larger stars through it at nighttime. Yet even if one placed so much "s'chach" on the sukkah that one cannot see the rays of the sun, the sukkah remains kosher (Ibid. 631:3). If, though, the amount of "s'chach" is so great that even rain cannot penetrate it, Rabbenu Tam (Rabbi Yaakov ben Meir Tam) holds that such a sukkah is not acceptable. This is because the sukkah is meant to be a temporary dwelling, and if the rain cannot penetrate its roof, it is more like an actual house. One must abide by this ruling where possible (Mishna Berurah 631:6).
The Structure of a Kosher Sukkah
A sukkah that is taller than twenty cubits (about 9.6 meters) is invalid. This is because the sukkah is meant to serve as a temporary dwelling, and a "s'chach" roof at such a height cannot be considered the roof of a temporary dwelling. If a sukkah is shorter than ten handbreadths (80 cm.), it is not kosher. This is because it is impossible to sit in it, and a sukkah must be suitable for sitting. Its width must be at least seven handbreadths (56 cm.), for if it is less than this, even one person cannot sit inside and eat his meal.
The height of the sukkah's walls must be at least ten handbreadths (80 cm.). They must be built on the ground, and if there is a space of three handbreadths between the ground and the base of the wall, the wall is invalid, for it is so wide open that even goats can make their way under it. It is permissible though, that there be space between the tops of the walls and the "s'chach"; if the walls themselves reach a height of ten handbreadths it is possible for the "s'chach" to be placed up to twenty cubits high, i.e., the maximum permissible height of a sukkah. And even if a large space is left between the top of the wall and the "s'chach" it remains valid, for we view the wall as if it continues to rise up to the height of the "s'chach" (Shulchan Arukh 630:9).
The sukkah must have two complete walls and a third whose length is at least one handbreadth. This law, however, is somewhat more complex. From the words of the Torah, we learn that a sukkah must have three walls, yet the Oral Tradition teaches that for the third wall one handbreadth is enough. This handbreadth has to be what the Sages refer to as "a wide handbreadth," i.e., slightly more than a handbreadth. This third wall must stand at a distance of no more than three handbreadths from the sukkah's second full wall. Any space that is less than three handbreadths is termed "lavud," or attached. In this manner, the third wall becomes a wall of four complete handbreadths - the minimum necessary requirement for a valid sukkah wall. The Sages also said that the remaining space of the wall must be made fit through what is known as "tzurat ha'petach," or the form of an opening (ibid. 639:2). The laws of concepts such as "lavud," and "tzurat ha'petach" are many and detailed, so much so that Rabbi Moshe Isserles (Rema) writes that the accepted custom is to build three complete walls, for not everyone is versed in the laws of sukkah walls (ibid. 630:5). Ideally, one should build a quality sukkah possessing four complete walls. The sukkah should also have a doorway that can be closed in order that it is comfortable for living purposes, protecting the one who dwells in it from the wind, sun, and animals.
A Sukkah under a House or a Tree
The sukkah must be situated under the open sky, so that the "s'chach", and not something else, covers the person dwelling in the sukkah. Therefore, a sukkah made indoors, under a roof, is invalid. Similarly, it is forbidden to make a sukkah under the branches of a tree.
It is permissible, though, to make a sukkah next to the walls of a high building. Even if the walls of the building are extremely high and prevent the sunlight from reaching the sukkah, it is kosher. This is because only a roof or branches which are directly above the "s'chach" can render a sukkah invalid; anything that is outside of the straight line running from the "s'chach" to the sky cannot invalidate the sukkah.
If the branches that are above the "s'chach" are very sparse and the sukkah's "s'chach" is so dense that even if the "s'chach" under the branches was removed, the remaining "s'chach" would be so thick that it provides more shade than sunlight, the sukkah remains kosher (ibid. Orach Chaim 621:1).
It is also permissible to build one's sukkah under clotheslines because their shade is very little, and since their purpose is not to provide shade, they do not invalidate the "s'chach" below.
Sitting under the Shade of the Sukkah
Fulfilling the mitzvah of the sukkah means sitting in the shade of a kosher sukkah. Therefore, if one spreads sheets under the 's'chach" for additional shade he has in fact invalidated the sukkah. It is permissible, though, for a person to sit in a sukkah wearing a big hat on his head, because the hat is an appendage to his body and is not seen as causing a separation between him and the "s'chach".
Similarly, it is permissible to hang different types of fruits and paper ornaments from the "s'chach", for the ornaments are an appendage to the "s'chach" and are not viewed as being a separation between the "s'chach" and those dwelling in the sukkah. One must make sure, though, that the ornaments hang within a four handbreadths length (32 cm.) of the "s'chach". Furthermore, even if the ornaments cover the entire "s'chach", so long as they hang within four handbreadths of the "s'chach", they are considered an appendage to the "s'chach" and do not render the sukkah invalid. If one accidentally hung an ornament that dangles down below the four handbreadth mark, so long as the width of the ornament is less than four handbreadths, it does not invalidate the sukkah. One must be careful, though, not to sit under it. If the width of the ornament is less than three handbreadths (24 cm.), though it is permissible to sit under it, it is preferable not to so. Rather, one should take care to raise all such ornaments to within four handbreadths of the "s'chach".
One who sleeps in a bed to which a canopy has been permanently attached does not fulfill the mitzvah of dwelling in the sukkah. If the canopy, however, is of a temporary nature, its status depends upon its height: If the canopy is lower than ten handbreadths, it lacks significance and is considered an appendage to the sukkah. One who sleeps in such a bed therefore fulfills the mitzvah of sukkah. If, though, its height is greater than ten handbreadths, the canopy possesses significance and one who sleeps under it does not fulfill the mitzvah of sukkah.
The space under a bed or a table inside the sukkah, because it is created unintentionally, is considered temporary. Its status therefore depends on its height. If the space underneath the table or bed is of a height less than ten handbreadths (80 cm.) one who sleeps under it fulfills the mitzvah of sukkah. If, however, the space is greater than ten handbreadths in height, one who sleeps under it does not fulfill the mitzvah of sukkah.
The same rule holds true when it comes to a bunk bed. If the space between the two beds is more than ten handbreadths, the person who sleeps in the bottom bed does not fulfill the mitzvah of sukkah. If the space, though, is less than ten handbreadths, one who sleeps in the bottom bed fulfills the mitzvah (see Pitchei Teshuva, 627:3).
If a protective covering is placed on the sukkah it is clearly rendered invalid, for the covering acts as a partition between the "s'chach" and the sky. Yet, after the covering has been removed, the sukkah again becomes valid. One must be careful, though, that when building the sukkah, the covering be rolled up to the side in such a manner that it does not constitute a partition between the "s'chach" and the sky. This is because there are Torah authorities who hold that if at the time of the construction of the sukkah the "s'chach" is overlaid with a covering, even after removing the covering the sukkah remains invalid. The reason for this is that the act of making a sukkah valid must be done by placing the "s'chach" upon it, and not by removing a covering from it (Bach, Mishna Berurah 626:18; but Rema is lenient, 626:3).
Happy holiday, Chag Sameach!!
