The SUKKAH should have at least three walls that are adjacent to each other and at least seven handsbreadths wide; the walls should preferably be solid (see 630:2-8;631:6-7). The walls may be made of any material that is durable, does not have a bad odor (see 630:1), and remains stationary under an ordinary wind (see 630:10). The walls must come within three handsbreadths of the ground and the roof, or must reach ten handsbreadths above the ground and their vertical extensions must pass within three handsbreadths of the roof; see 630:9.
The roof must be made of things that grow from the ground, are not attached to the ground, are not susceptible to impurity (generally, which have not been turned into finished or nearly-finished products), are durable (see 629:12), and are not ordinarily used for other purposes (see 629:1-13,15-18); things that have a bad odor or whose parts frequently fall off must also not be used (629:14). The roof should not be supported, fastened or held down by items which are susceptible to impurity, but such items may be used to support or fasten the beams which support the roof (see 629:7-8)
The roof material must cover the majority of all parts of the horizontal roof area; overall, it must produce slightly more shade than sun; see 631:1-2,4-5. Preferably the SUKKAH should be roofed lightly enough that stars are visible through it. If it is too heavily roofed for this it is acceptable, but if the covering is so thick that even heavy rains do not penetrate it, according to many authorities it is not valid (see 631:3 and MB 6). On a roof that has gaps or is partly covered with unacceptable material see 626:1;631:8-9;632:1-4; on a roofless SUKKAH whose walls meet at the top see 631:10.
The roof must not begin more than 20 cubits or less than 10 handsbreadths above the floor of the SUKKAH; see 630:13 and 633:1-10. Horizontally, the SUKKAH must be large enough to contain a square of size 7 by 7 handsbreadths; see 634:1-3. On a SUKKAH under a tree, inside a house, or under a removable roof see 626:1-3; on canopies inside a SUKKAH see 627:1-4; on one SUKKAH under another see 628:1; on a SUKKAH carried by a wagon, ship, or animal, or built in a tree, see 628:2-3.
Decorations hung from the SUKKAH’s roof within four handsbreadths of the roof do not form an obstruction between the SUKKAH’s roof and interior. If they hang further than four handsbreadths and they are additionally 4×4 handsbreadths wide, they do form an obstruction. It is preferable, however, that no decorations hang below four handsbreadths of the roof; see 627:4.
The SUKKAH should ideally be built expressly for the holiday, but it is also acceptable if built only for shade. In the latter case, one should preferably lift up a 1×1 area of the roof and place it down again expressly for the holiday. The same is true if a SUKKAH was built more than 30 days before the holiday (when it was not evident that it was built for the holiday); (see 635:1 and 636:1). At least part of the walls must be made before the roof is made (see 626:2;629:15). A SUKKAH may be built even on the intermediate days of the holiday (637:1). A person may use more than one SUKKAH (637:1), and may use another person’s SUKKAH, or build a SUKKAH on another person’s land, with his permission (see 637:2-3).
A person must not derive benefit, until after the holiday, from any part of a SUKKAH that has been used for the holiday (638:1;667:1); on deriving benefit from SUKKAH decorations see 638:2. A person should not take down his SUKKAH after eating there on the last day, but things kept in the SUKKAH may be brought into the house (666:1). On using the SUKKAH on the eighth (or ninth) day, or after the holiday, see 666:1 and 668:1; on leaving it at the end of the holiday see 667:1.
A person should eat and sleep in the SUKKAH; during the entire holiday, the SUKKAH should be his primary residence and his house should be secondary, and the SUKKAH should be treated respectfully (639:1,7;640:4). On which furniture and utensils should be kept in the SUKKAH see 634:4 and 639:1; on sleeping there see 639:2; on what must be eaten or drunk there see 639:2-3; on studying and praying there see 639:4. A person is required to eat in the SUKKAH on the first night of the holiday; see 639:3,5. A person may leave the SUKKAH if it would be uncomfortable to stay there (for example, if it rains), except on the first night; see 639:5-7 and 640:4. On those who are exempt from using a SUKKAH see 640:1-10.
Shulchan Aruch, Copyright (c) 2000 Project Genesis, Inc.