SECTION 626 Laws Relating to the Construction of a Sukkah under a Tree or under a Roof. (1–21)

סימן תרכו הָעוֹשֶׂה סֻכָּה תַּחַת הָאִילָן אוֹ תַּחַת הַגָּג וּבוֹ כ"א סְעִיפִים:

1 One can fulfill his obligation [to dwell in a sukkah] only with a sukkah that is made for the purpose of shade alone,1 like the Clouds of Glory.2 If, however, it is also made with the intent of serving as a dwelling, i.e., to enable one to live there in a permanent manner and not only to take shelter in its shade, or if it is also intended for private use, such as for a storehouse, or for another function that requires a secluded place, or if it was also made “as a protective haven from downpours of rain,”3 [it is not halachically acceptable].

Any structure that was not made for shade alone is not deemed a sukkah but a house. A house is designated for all of these purposes, but the Torah specified a sukkah, not a house.

אאֵין אָדָם יוֹצֵא יְדֵי חוֹבָתוֹ אֶלָּא בְּסֻכָּה שֶׁאֵינָהּ עֲשׂוּיָה אֶלָּא לְצֵלא,1 בִּלְבַד דֻּגְמַת עַנְנֵי כָּבוֹד,2 אֲבָל אִם הִיא עֲשׂוּיָה גַּם לְדִירָה דְּהַיְנוּ לָדוּר בָּהּ בִּקְבִיעוּתב וְלֹא לְהִסְתּוֹפֵף בְּצִלָּהּ בִּלְבַד, אוֹ שֶׁעֲשׂוּיָה גַּם לְהִשְׁתַּמֵּשׁ בָּהּ תַּשְׁמִישׁ שֶׁל צְנִיעוּתג כְּגוֹן לְאוֹצָר,ד אוֹ שְׁאָר תַּשְׁמִישׁ שֶׁצָּרִיךְ לַעֲשׂוֹתוֹ בְּמָקוֹם צָנוּעַ, אוֹ שֶׁהִיא עֲשׂוּיָה גַּם לְמַחְסֶה וּלְמִסְתּוֹר מִזֶּרֶם וּמִמָּטָר,ה,3 כָּל שֶׁאֵינָהּ עֲשׂוּיָה לְצֵל בִּלְבַד – אֵין זוֹ סֻכָּה אֶלָּא בַּיִת,ו שֶׁהֲרֵי הַבַּיִת הוּא מְיֻחָד לְכָל דְּבָרִים אֵלּוּ, וְהַתּוֹרָה אָמְרָה סֻכָּה וְלֹא בַּיִת:ז

2 A sukkah must be under the open sky, as were the Clouds of Glory. If a sukkah was constructed within a house it is invalid,4 because [its] shade serves no purpose; even without the s’chach,5 there is shade because of the roof of the house.

The same law applies if a sukkah is made under a tree,4 or under any other materials that are unacceptable as s’chach, as explained in sec. 631.6 [This restriction applies] whether the sukkah existed before it was covered by the material whose shade is halachically unacceptable, or whether that invalid [covering] was present before the sukkah was constructed. In either case [the sukkah is invalid] because the shade brought about by the sukkah now serves no purpose, for the shade brought about by the other material is above it.

ב וּצְרִיכָה שֶׁתְּהֵא הַסֻּכָּה תַּחַת אֲוִיר הַשָּׁמַיִםח דֻּגְמַת עַנְנֵי הַכָּבוֹד,ט אֲבָל אִם עֲשָׂאָהּ בְּתוֹךְ הַבַּיִת – פְּסוּלָה,י,4 לְפִי שֶׁאֵין צֵל הַסֻּכָּה מְשַׁמֵּשׁ כְּלוּם,יא שֶׁאַף בִּלְעֲדֵי הַסְּכָךְ5 יֵשׁ כָּאן צֵל מֵחֲמַת תִּקְרַת הַבַּיִת. וְכֵן הַדִּין בְּעוֹשֶׂה סֻכָּה תַּחַת הָאִילָן,יב,4 אוֹ תַּחַת שְׁאָר דְּבָרִים הַפְּסוּלִים לִסְכָךְ שֶׁיִּתְבָּאֵר בְּסִימָן תרל"א,יג,6 בֵּין שֶׁקָּדְמָה הַסֻּכָּה לַדָּבָר הַפָּסוּל הַמַּאֲהִיל עָלֶיהָ בֵּין שֶׁקָּדַם הַדָּבָר הַפָּסוּל לְהַסֻּכָּה,יד שֶׁמִּכָּל מָקוֹם עַכְשָׁו אֵין צֵל הַסֻּכָּה מְשַׁמֵּשׁ כְּלוּם, כֵּיוָן שֶׁהַצֵּל הָעֶלְיוֹן עָלָיו:

3 Such a sukkah is therefore invalid, even if the shadow that [its s’chach7] casts [on the floor] exceeds the sunlit area,8 without including at all the shade from the higher, [invalid] covering; i.e., even if the shadow cast by the higher covering were removed, the shadow cast by [the sukkah] would exceed its sunlit area.

[Moreover,] even if the shade from the higher, [invalid] covering alone is so limited that if the shade from the lower [covering] — i.e., the s’chach of the sukkah — was removed, the [floor] area remaining open to the sunlight admitted by the higher [covering] would exceed its shaded area, the sukkah is nevertheless invalid. [The rationale is that] the shade from the higher, invalid [covering] nullifies the shade produced by the s’chach directly beneath it; [that s’chach] serves no purpose, since the higher, invalid [covering] produces shade over the same place over which [the s’chach] produces shade. [See fig. 1.] We therefore consider the shade [on the floor] caused by the valid s’chach as if it were reduced to the same extent as the area [of s’chach] that is shaded by the higher, [invalid] covering. Hence this is as if the [latter] area [of s’chach], which is shaded by the higher, [invalid] covering, was [open to the sky, and the corresponding floor area was] sunlit. The sunlit area of the sukkah [may] thus exceed its shaded part [thus invalidating the sukkah].9

ג לְפִיכָךְ אֲפִלּוּ אִם צֵל הַסֻּכָּה7 מְרֻבֶּה מֵחַמָּתָהּ8 בְּלֹא צֵרוּף צֵל הָעֶלְיוֹן כְּלָל, דְּהַיְנוּ שֶׁאֲפִלּוּ אִם יִנָּטֵל צֵל הָעֶלְיוֹן מִכָּאן יִהְיֶה צִלָּתָהּ מְרֻבֶּה מֵחַמָּתָהּ – אַף עַל פִּי כֵן פְּסוּלָה. וַאֲפִלּוּ אִם צֵל הָעֶלְיוֹן בִּלְבַד הוּא מְעַט מִזְעָר, בְּעִנְיָן שֶׁאִם יִנָּטֵל צֵל הַתַּחְתּוֹן דְּהַיְנוּ צֵל הַסְּכָךְ שֶׁעַל גַּבֵּי הַסֻּכָּה תִּהְיֶה חַמָּתוֹ שֶׁל הָעֶלְיוֹן מְרֻבָּה מִצִּלָּתוֹ – אַף עַל פִּי כֵן פְּסוּלָה,טו דְּכֵיוָן שֶׁצֵּל הָעֶלְיוֹן שֶׁהוּא פָּסוּל עוֹמֵד לְמַעְלָה – הֲרֵי הוּא מְבַטֵּל צֵל הַסְּכָךְ שֶׁתַּחְתָּיו כְּנֶגְדּוֹ מַמָּשׁ, שֶׁהֲרֵי אֵינוֹ מְשַׁמֵּש כְּלוּם, כֵּיוָן שֶׁהָעֶלְיוֹן מֵצֵל עַל מָקוֹם שֶׁהוּא מֵצֵל,טז וּלְפִיכָךְ אָנוּ רוֹאִים כְּאִלּוּ נִטַּל וְנֶחְסַר מִן צֵל הַסְּכָךְ הַכָּשֵׁריז כְּשִׁעוּר צֵל הָעֶלְיוֹן שֶׁמֵּצֵל עַל הַסֻּכָּה, וּכְאִלּוּ הָיָה הַמָּקוֹם הַזֶּה שֶׁהָעֶלְיוֹן מֵצֵל עָלָיו מְקוֹם חַמָּה, וְתִהְיֶה הַסֻּכָּה חַמָּתָהּ מְרֻבָּה מִצִּלָּתָהּ:יח,9


Fig. 1:
In this diagram, 60% of the floor area is shaded by valid s’chach. However, the uppermost covering is invalid, since it is made of boards that are more than four tefachim wide (see sec. 629:29). The shadow it casts – overlapping (say) 30% of the area – nullifies the shade produced by the corresponding amount of valid s’chach directly beneath it. Hence only [60% – 30% =] 30% of the floor area is now shaded by valid s’chach. Since this is less than half of the floor area, this sukkah is invalid. (See sec. 626:3.)
Fig. 1: In this diagram, 60% of the floor area is shaded by valid s’chach. However, the uppermost covering is invalid, since it is made of boards that are more than four tefachim wide (see sec. 629:29). The shadow it casts – overlapping (say) 30% of the area – nullifies the shade produced by the corresponding amount of valid s’chach directly beneath it. Hence only [60% – 30% =] 30% of the floor area is now shaded by valid s’chach. Since this is less than half of the floor area, this sukkah is invalid. (See sec. 626:3.)

Fig. 2:
Since the valid s’chach here is thicker, it casts a shade over (say) 85% of the floor area. Even if one now deducts the amount of shade produced by the overlapping invalid material, the floor area that is shaded by valid s’chach still exceeds the sunlit area. (85% – 30% = 55%.) This sukkah is thus valid. (See sec. 626:4.)
Fig. 2: Since the valid s’chach here is thicker, it casts a shade over (say) 85% of the floor area. Even if one now deducts the amount of shade produced by the overlapping invalid material, the floor area that is shaded by valid s’chach still exceeds the sunlit area. (85% – 30% = 55%.) This sukkah is thus valid. (See sec. 626:4.)

4 If, however, the shade produced by [the s’chach of] the sukkah is so extensive that even if an area [of s’chach] equivalent to the part shaded by the higher, [invalid covering] were to be removed and the remaining area were open to sunlight, the shaded part of the sukkah would nevertheless exceed its sunlit area, the sukkah is valid. [See fig. 2.]

ד אֲבָל אִם צֵל הַסֻּכָּה הוּא מְרֻבֶּה מְאֹד, בְּעִנְיָן שֶׁאֲפִלּוּ אִם יִנָּטֵל מִמֶּנָּה כְּשִׁעוּר צֵל הָעֶלְיוֹן וְיִהְיֶה הַמָּקוֹם שֶׁהָעֶלְיוֹן מֵצֵל עָלָיו מְקוֹם חַמָּה וְאַף עַל פִּי כֵן תִּהְיֶה הַסֻּכָּה צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ – כְּשֵׁרָה:יט

5 The above applies when the material that is invalid as s’chach was positioned above the valid s’chach. [Different rules apply] if [the two] were intermingled; for example, if there was a tree that cast a shadow over a sukkah, and one lowered its branches and mixed them together [with the acceptable s’chach. See p. 252, fig. 3.]

If there is much more10 of the valid s’chach than of the material that is invalid for s’chach, the invalid material becomes batel — insignificant and [therefore] nullified — vis-à-vis the majority [of the valid s’chach]. Moreover, even if the valid s’chach is placed upon the material that is invalid as s’chach, it is considered as intermingled and is nullified vis-à-vis the majority [of the valid s’chach].11

[In this instance,] the material that is invalid as s’chach is distinct from the valid [s’chach]; it is not completely intermingled, and could be removed. Nevertheless, it is nullified. [This represents an exception to the accepted pattern.] With regard to all the prohibitions of the Torah, [we follow the principle that] if the forbidden substance is recognizable and can be removed from the mixture, it does not become nullified, even if there is 1000 times more of the permitted substance.12 [In the case of food, for example,] such a mixture may not be eaten, lest one encounter the actual forbidden substance whose existence was not nullified, because it could have been removed. In this instance, however, [that principle is not followed]. For no benefit is gained from the forbidden material; even if the substance that is invalid as s’chach were to be removed from the sukkah, there would be enough valid s’chach for the shade of the sukkah to exceed its sunlit area. We must nullify the invalid material vis-à-vis the large amount [of the valid s’chach] only so that [the invalid material] will not disqualify the valid s’chach with which it is combined.

ה וְכָל זֶה כְּשֶׁהָיָה הַסְּכָךְ פָּסוּל לְמַעְלָה עַל הַסְּכָךְ כָּשֵׁר, אֲבָל אִם הָיוּ מְעֹרָבִים זֶה בָּזֶה, כְּגוֹן אִילָן שֶׁהָיָה מֵצֵל עַל הַסֻּכָּה שֶׁלְּמַטָּה מִמֶּנּוּ וְהִשְׁפִּיל עֲנָפָיו לְמַטָּהכ וְעֵרְבָן, אִם הַסְּכָךְ הַכָּשֵׁר הוּא מְרֻבֶּה הַרְבֵּה10 מִן הַסְּכָךְ הַפָּסוּל הַמְעֹרָב בּוֹ – הֲרֵי הַפָּסוּל נִתְבַּטֵּל בָּרֹב,כא אַף אִם הִנִּיחַ סְכָךְ הַכָּשֵׁר עַל סְכָךְ הַפָּסוּל – נִקְרָא עִרְבּוּב וּבָטֵל בְּרֹב,כב,11 וְאַף עַל פִּי שֶׁסְּכָךְ הַפָּסוּל הוּא נִכָּר בֵּין הַכָּשֵׁר וְאֵינוֹ מְעֹרָב יָפֶה וְהוּא יָכוֹל לַהֲסִירוֹ מִשָׁם – אַף עַל פִּי כֵן הוּא בָּטֵל.כג

וְאַף עַל פִּי שֶׁבְּכָל אִסּוּרִין שֶׁבַּתּוֹרָה אִם הוּא מַכִּיר אֶת הָאִסּוּר וְיָכוֹל לַהֲסִירוֹ מִן הַתַּעֲרוֹבוֹת אֵינוֹ בָּטֵלכד אֲפִלּוּ בְּאֶלֶף,כה,12 הַיְנוּ שֶׁאָסוּר לֶאֱכֹל אֶת הַתַּעֲרוֹבוֹת, שֶׁלֹּא יִפְגַּע בְּגוּף הָאִסּוּר עַצְמוֹ, שֶׁלֹּא נִתְבַּטֵּל כֵּיוָן שֶׁיָּכוֹל לַהֲסִירוֹ מִשָּׁם, אֲבָל כָּאן אֵינוֹ נֶהֱנֶה כְּלָל מִן הָאִסּוּר, שֶׁהֲרֵי אַף אִם יִנָּטֵל סְכָךְ הַפָּסוּל מִן הַסֻּכָּה יִהְיֶה צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ מֵחֲמַת סְכָךְ הַכָּשֵׁר,כו וְאֵין אָנוּ צְרִיכִים לְבַטֵּל אֶת הַפָּסוּל בְּרֹב אֶלָּא כְּדֵי שֶׁלֹּא יִהְיֶה לוֹ כֹּחַ לִפְסֹל אֶת הַסְּכָךְ הַכָּשֵׁר הַמְעֹרָב עִמּוֹ:כז

Fig. 3:
Sec. 626:5 describes a case in which the shade over 60% of the floor area remains valid, despite the presence of 30% shade produced by the intermingled, invalid covering. The sukkah is thus valid.
Fig. 3: Sec. 626:5 describes a case in which the shade over 60% of the floor area remains valid, despite the presence of 30% shade produced by the intermingled, invalid covering. The sukkah is thus valid.

6 However, if so little shade is produced by valid [s’chach] that when the shade produced by the [intermingled] invalid material is removed from the sukkah, the shade [on the floor] will not exceed the sunlit area, [the sukkah] is invalid. [See fig. 4.] For the shade produced by the invalid material cannot be combined with the shade produced by valid [s’chach] to complete its minimum measure. The rationale [for this stringency] is that [the invalid material] has not yet been entirely nullified, for it could be removed.

ו אֲבָל אִם צֵל הַכָּשֵׁר הוּא מְעַט בְּעִנְיָן שֶׁאִם יִנָּטֵל צֵל הַפָּסוּל מִן הַסֻּכָּה לֹא יְהֵא צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ – הֲרֵי הִיא פְּסוּלָה, לְפִי שֶׁאֵין צֵל הַפָּסוּל מִצְטָרֵף לְהַשְׁלִים הַשִּׁעוּר לְצֵל הַכָּשֵׁר, כֵּיוָן שֶׁלֹּא נִתְבַּטֵּל עֲדַיִן בִּטּוּל גָּמוּר, שֶׁהֲרֵי יָכוֹל לַהֲסִירוֹ מִשָׁם:כח

Fig. 4:
In this sukkah, the valid s’chach is so sparse that its shade covers only (say) 40% of the floor area. Since in this case the shade (say 30%) produced by the invalid material is disregarded (see sec. 626:6), the sukkah is invalid, because less than half of its floor area is shaded by valid s’chach.
Fig. 4: In this sukkah, the valid s’chach is so sparse that its shade covers only (say) 40% of the floor area. Since in this case the shade (say 30%) produced by the invalid material is disregarded (see sec. 626:6), the sukkah is invalid, because less than half of its floor area is shaded by valid s’chach.

7 All of the above applies when the invalid material that is intermingled with the valid s’chach is so flimsy and insubstantial that the sunlit area [in the sukkah] exceeds the shaded area.13 If, however, [the invalid material] causes the shade to exceed the sunlit area, its nullification vis-à-vis the greater quantity [of valid s’chach] is not effective in preventing its shade from disqualifying the sukkah. For the valid s’chach serves no function in the place where the invalid material would provide shade [even] if [the valid s’chach] were not mixed with it, for the shade [produced by the invalid material] exceeds the sunlit area [of the sukkah. See fig. 5.]

Such a sukkah is therefore acceptable only if it has so much valid s’chach that if we would remove [from it] an amount that is equivalent to the invalid material that is intermingled with it, the shaded area within the sukkah would still exceed its sunlit area.14 [See fig. 6.]

ז וְכָל זֶה כְּשֶׁהַסְּכָךְ הַפָּסוּל הַמְעֹרָב בַּכָּשֵׁר הוּא בְּעַצְמוֹ קַל וְקָלוּשׁ בְּעִנְיָן שֶׁחַמָּתוֹ מְרֻבָּה מִצִּלָּתוֹ,13 אֲבָל אִם צִלָּתוֹ מְרֻבָּה מֵחַמָּתוֹ – אֵין בִּטּוּל בְּרֹב מוֹעִיל לוֹ שֶׁלֹּא יִפְסֹל אֶת הַסֻּכָּה בְּצִלּוֹ,כט כֵּיוָן שֶׁצֵּל הַכָּשֵׁר אֵינוֹ מְשַׁמֵּשׁ כְּלוּםל בְּמָקוֹם שֶׁהַפָּסוּל הָיָה יָכוֹל לִהְיוֹת מֵצֵל שָׁם אִם לֹא נִתְעָרֵב שָׁם, כֵּיוָן שֶׁצִּלָּתוֹ מְרֻבָּה מֵחַמָּתוֹ, וְלָכֵן אֵין הַסֻּכָּה כְּשֵׁרָה, אֶלָּא אִם כֵּן יֵשׁ בָּהּ סְכָךְ כָּשֵׁר הַרְבֵּה כָּל כָּךְ עַד שֶׁאִם יִנָּטֵל מֵהַסְּכָךְ הַכָּשֵׁר כְּשִׁעוּר הַסְּכָךְ הַפָּסוּל הַמְעֹרָב בּוֹ הָיְתָה הַסֻּכָּה צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ:לא,14

Fig. 5:
In this sukkah, described in the first paragraph of sec. 626:7, there is enough valid s’chach to cast a shadow over (say) 90% of the floor area. However, so much invalid material is intermingled with it that it alone would be able to cast a shadow over (say) 60% of the floor area. This invalid material is therefore not nullified vis-à-vis the greater quantity of valid s’chach (90% – 60% = 30%). The sukkah is thus invalid.
Fig. 5: In this sukkah, described in the first paragraph of sec. 626:7, there is enough valid s’chach to cast a shadow over (say) 90% of the floor area. However, so much invalid material is intermingled with it that it alone would be able to cast a shadow over (say) 60% of the floor area. This invalid material is therefore not nullified vis-à-vis the greater quantity of valid s’chach (90% – 60% = 30%). The sukkah is thus invalid.

Fig. 6:
The second paragraph of sec. 626:7 explains why this sukkah is valid. Its s’chach is so plentiful that even if we were to remove an amount equivalent to the invalid material intermingled with it (150% – 60% = 90%), the greater part of the floor area would still be shaded.
Fig. 6: The second paragraph of sec. 626:7 explains why this sukkah is valid. Its s’chach is so plentiful that even if we were to remove an amount equivalent to the invalid material intermingled with it (150% – 60% = 90%), the greater part of the floor area would still be shaded.

8 When does the above apply? When the valid s’chach and the invalid material are intermingled, or when the invalid material is positioned below the valid s’chach. [In such an instance,] the valid s’chach must exceed the invalid material so that [the latter] will be [outweighed and hence] nullified and [thus] will not disqualify the sukkah by its shade.

If, however, both [the valid s’chach and the invalid material] were placed on the sukkah separately, one next to the other, without being mixed together at all, there is no need that the valid s’chach exceed the invalid material. Even if they are equal in amount the sukkah is valid, for, as explained in sec. 631[:10], this is a halachah transmitted to Moshe at Sinai.15

ח בַּמֶּה דְּבָרִים אֲמוּרִים? כְּשֶׁהַכָּשֵׁר וְהַפָּסוּל הֵן מְעֹרָבִין, אוֹ שֶׁהַפָּסוּל הוּא מֻנָּח לְמַטָּה מִן הַכָּשֵׁר, שֶׁאָז צָרִיךְ שֶׁיְּהֵא בַּכָּשֵׁר רֹב כְּנֶגֶד הַפָּסוּל כְּדֵי לְבַטְּלוֹ שֶׁלֹּא יִפְסֹל אֶת הַסֻּכָּה בְּצִלּוֹ, אֲבָל אִם הָיוּ מֻנָּחִין עַל הַסֻּכָּה כָּל אֶחָד וְאֶחָד בִּפְנֵי עַצְמוֹ זֶה בְּצַד זֶה וְאֵינָן מְעֹרָבִין כְּלָל – אֵין צָרִיךְ שֶׁיִּהְיֶה בַּכָּשֵׁר רֹב כְּנֶגֶד הַפָּסוּל, אֶלָּא אֲפִלּוּ אִם הֵם מֶחֱצָה עַל מֶחֱצָה גַּם כֵּן – הַסֻּכָּה הִיא כְּשֵׁרָה,לב שֶׁכָּךְ הִיא הֲלָכָה לְמֹשֶׁה מִסִּינַילג,15 כְּמוֹ שֶׁיִּתְבָּאֵר בְּסִימָן תרל"א,לד עַיֵּן שָׁם:

9 (16Some authorities differ with this entire approach. They maintain that if the invalid material is intermingled with valid s’chach and they are both of the same type, and thus the invalid material is not at all distinct, [there is room for leniency]. For example: one built a sukkah under a tree, bent down [its] branches, and lowered them [so that he could] mix them together with the detached s’chach on top of the sukkah. Although it is possible for him to remove the prohibited material by raising the branches up to the trunk of the tree, as long as they are mixed together [with the valid s’chach] and are not distinct, they are nullified vis-à-vis the majority [of valid s’chach. Moreover,] they may be combined together with it to fill the [required] measure, [so that] the shade [within the sukkah] will exceed the sunlit area.17 (This differs from the first opinion.)18

[In this situation,] the invalid material that is mixed [with the valid s’chach] must be so flimsy and insubstantial that the sunlit area [within the sukkah] exceeds its shade. If, however, the shade [from the invalid material] exceeds the sunlit area [within the sukkah], it cannot be combined [as part of the valid s’chach] and be counted towards the measure that is required to make the shade [within the sukkah] exceed its sunlit area.19

Nevertheless, if the shade [within] the sukkah exceeds its sunlit area without counting the shade cast by the invalid material, [the sukkah] is never disqualified by the invalid material, even though [its quantity alone would suffice to make] the shade exceed the sunlit area.20

ט (וְיֵשׁ16 חוֹלְקִין עַל כָּל זֶהלה וְאוֹמְרִים שֶׁאִם הַפָּסוּל מְעֹרָב בַּכָּשֵׁר וּשְׁנֵיהֶן הֵן מִין אֶחָד שֶׁאֵין הַפָּסוּל נִכָּר כְּלָל, כְּגוֹן הָעוֹשֶׂה סֻכָּתוֹ תַּחַת הָאִילָן וְהִשְׁפִּיל עַנְפֵי הָאִילָן וְהוֹרִידָן לְמַטָּה וְעֵרְבָן עִם הַסְּכָךְ הַתָּלוּשׁ שֶׁעַל גַּבֵּי הַסֻּכָּה,לו אַף עַל פִּי שֶׁהוּא יָכוֹל לְהָסִיר אֶת הָאִסּוּר, דְּהַיְנוּ שֶׁיַּגְבִּיהַּ אֶת הָעֲנָפִים לְעִקַּר הָאִילָן, מִכָּל מָקוֹם כָּל זְמַן שֶׁהֵן מְעֹרָבִין יַחַד וְאֵין נִכָּרִיןלז – הֵן בְּטֵלִים בְּרֹב הַכָּשֵׁר, וּמִצְטָרְפִין עִמּוֹ לְהַשְׁלִים לְשִׁעוּר צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ17 (דְּלֹא כְּמוֹ שֶׁנִּתְבָּאֵר בַּדֵּעָה הָרִאשׁוֹנָה18).*

וְהוּא שֶׁיְּהֵא סְכָךְ פָּסוּל הַמְעֹרָב דַּק וְקָלוּשׁ בְּעִנְיָן שֶׁיְּהֵא חַמָּתוֹ מְרֻבָּה מִצִּלָּתוֹ, אֲבָל אִם צִלָּתוֹ מְרֻבָּה מֵחַמָּתוֹ – אֵינוֹ מִצְטָרֵף לְהַשְׁלִים לְשִׁעוּר צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ.לח,19 אֲבָל אִם הַסֻּכָּה הִיא צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ בְּלֹא צֵרוּף צֵל סְכָךְ הַפָּסוּל – אֵינָהּ נִפְסֶלֶת לְעוֹלָם מֵחֲמַת צֵל סְכָךְ הַפָּסוּל, אַף עַל פִּי שֶׁצִּלָּתוֹ מְרֻבָּה מֵחַמָּתוֹ:לט,20

* וְאַף עַל פִּי שֶׁבְּכָל אִסּוּרִים שֶׁבַּתּוֹרָה אִם יָכוֹל לְהָסִיר אֶת הָאִסּוּר אֵינוֹ מִתְבַּטֵּל בְּרֹב, אֲבָל כָּאן הֲלָכָה לְמֹשֶׁה מִסִּינַי הוּא שֶׁאֵין צָרִיךְ לִהְיוֹת כָּל הַסְּכָךְ הַצָּרִיךְ לַסֻּכָּה שֶׁיְּהֵא סְכָךְ כָּשֵׁר אֶלָּא שֶׁיִּהְיֶה הָרֹב כָּשֵׁר,מ וְהַשְּׁאָר אַף עַל פִּי שֶׁהוּא פָּסוּל – אַף עַל פִּי כֵן הַסֻּכָּה מִתְכַּשֶּׁרֶת בּוֹ, וְאִם כֵּן אֵין עַל הַמִּעוּט שֵׁם סְכָךְ פָּסוּל, אֶלָּא גַּם הוּא חוֹזֵר לִהְיוֹת סְכָךְ כָּשֵׁר עַל יְדֵי רֹב הַכָּשֵׁר שֶׁעִמּוֹ.מא וּלְפִיכָךְ מֻתָּר לְעָרֵב וּלְבַטֵּל סְכָךְ פָּסוּל בַּכָּשֵׁר לְכַתְּחִלָּה,מב מַה שֶּׁאֵין כֵּן בִּשְׁאָר אִסּוּרִין שֶׁאֵין מְבַטְּלִין אִסּוּר לְכַתְּחִלָּה,מג לְפִי שֶׁאֵין שֵׁם אִסּוּר כְּלָל עַל הַמִּעוּט הַפָּסוּל הַמְעֹרָב בַּכָּשֵׁר.

10 [These authorities also differ] when the invalid material is not intermingled with the valid s’chach, but is positioned overhead and casts its shadow over [it]. If the shade [within] the sukkah does not exceed its sunlit area without counting the shade [from] the invalid material — even when the sunlit area [within the sukkah] exceeds its shade if the invalid material alone is [considered] — the sukkah is invalid.21 [The rationale is that it is] the invalid material that completes the [required] measure [of shade].

If, however, the shade [from the valid s’chach] exceeds the sunlit area without the addition of the shade from the invalid material, [the sukkah] is valid.22 [This applies] even when the shade from the invalid material exceeds the sunlit area [within the sukkah].

Primacy should be given to the first opinion with regard to all of the above. Nevertheless, in a pressing situation in which one does not have another sukkah and he cannot correct such a sukkah and make it valid, he may rely on the latter opinion23 so that he will not negate [the observance of] the mitzvah of sukkah.24

י וְאִם סְכָךְ הַפָּסוּל אֵינוֹ מְעֹרָב עִם סְכָךְ הַכָּשֵׁר אֶלָּא הוּא עוֹמֵד לְמַעְלָה וּמֵצֵל עַל הַכָּשֵׁר, אִם אֵין צֵל הַסֻּכָּה מְרֻבֶּה מֵחַמָּתָהּ בְּלֹא צֵרוּף צֵל הַפָּסוּל, אַף עַל פִּי שֶׁהַפָּסוּל חַמָּתוֹ מְרֻבָּה מִצִּלָּתוֹ – אַף עַל פִּי כֵן הֲרֵי זוֹ פְּסוּלָה,21 שֶׁהֲרֵי סְכָךְ פָּסוּל מַשְׁלִימָהּ לְשִׁעוּרָהּ,מד אֲבָל אִם צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ בְּלֹא צֵרוּף צֵל הַפָּסוּל,מה אַף עַל פִּי שֶׁהַפָּסוּל צִלָּתוֹ מְרֻבָּה מֵחַמָּתוֹ – הֲרֵי זוֹ כְּשֵׁרָה.מו,22

וְהָעִקָּר כַּסְּבָרָא הָרִאשׁוֹנָה בְּכָל זֶה.מז וּמִכָּל מָקוֹם, בִּשְׁעַת הַדְּחָקמח שֶׁאֵין לוֹ סֻכָּה אַחֶרֶת, וְגַם אִי אֶפְשָׁר לוֹ לְתַקֵּן סֻכָּה זוֹ וּלְהַכְשִׁירָהּ – יֵשׁ לִסְמֹךְ עַל סְבָרָא הָאַחֲרוֹנָה,23 שֶׁלֹּא לְהִתְבַּטֵּל מִמִּצְוַת סֻכָּה:24

11 If one desires to cut off [the branches of] a tree [that had been placed on a sukkah] to make them valid for s’chach, as will be explained in sec. 629[:20], he must move all [the branches of] the tree. Note the rationale explained there.25

יא אִם רוֹצֶה לִקְצֹץ אֶת הָאִילָן לְהַכְשִׁירוֹ לְסִכּוּךְ – יִתְבָּאֵר בְּסִימָן תרכ"טמט שֶׁצָּרִיךְ לְנַעֲנֵעַ אֶת כָּל הָאִילָן, עַיֵּן שָׁם הַטַּעַם:25

12 It is permitted to make a sukkah in a house below a roof from which the shingles were removed so that a sukkah be made there, even if the wood or the beams on which the shingles rest remain. [It would appear that] the wood and the beams are not valid as s’chach, since they were affixed in the roof to support the shingles and not for the purpose of shade alone. Nevertheless, one may sit under the wood or the beams themselves. [The rationale is that] since one performed an action and removed the shingles with the intent of making a sukkah for shade, it is considered as if he performed an action with regard to the wood or the beams themselves and prepared them for the sake of the sukkah. And they are acceptable for use as s’chach, for they are products of the earth and are not susceptible to ritual impurity. The fact that they are attached26 is not significant. For an entity that was detached and then attached [to the ground] is acceptable for [the s’chach of] a sukkah, as explained in sec. 629.27

The act [of removing the shingles] makes [the remaining beams or supports of wood] themselves valid as s’chach. [Additional] valid s’chach could therefore be placed upon them and they may be counted together with [it] to make up the quantity required to make the shade [within the sukkah] exceed its sunlit area. Therefore even when — as in the present instance — the s’chach was not placed upon them, but under them, in the house, one may sit directly under them, for they are valid s’chach.

יב מֻתָּר לַעֲשׂוֹת סֻכָּה לְמַטָּה בַּבַּיִת תַּחַת הַגָּג שֶׁהֵסִירוּ הָרְעָפִים מִמֶּנּוּ כְּדֵי לַעֲשׂוֹת סֻכָּה, אַף עַל פִּי שֶׁנִּשְׁאֲרוּ עֲדַיִן הָעֵצִים אוֹ הַקּוֹרוֹת שֶׁהָרְעָפִים מֻנָּחִים עֲלֵיהֶם.נ

וּמֻתָּר לֵישֵׁב תַּחַת הָעֵצִים אוֹ הַקּוֹרוֹת עַצְמָןנא אַף עַל פִּי שֶׁהֵם סְכָךְ פָּסוּל, שֶׁהֲרֵי לֹא נִקְבְּעוּ בַּגָּג לְשֵׁם צֵל בִּלְבַד אֶלָּא כְּדֵי לָתֵת עֲלֵיהֶם אֶת הָרְעָפִים,נב מִכָּל מָקוֹם כֵּיוָן שֶׁעָשָׂה מַעֲשֶׂה וְהֵסִיר אֶת הָרְעָפִיםנג לְשֵׁם עֲשִׂיַּת סֻכָּה לְצֵל – הֲרֵי זֶה כְּאִלּוּ עָשָׂה מַעֲשֶׂה בְּגוּף הָעֵצִים אוֹ הַקּוֹרוֹת וְהִתְקִינָם לְשֵׁם סֻכָּה,נד שֶׁהֲרֵי הֵם כְּשֵׁרִים לְסִכּוּךְ, שֶׁהֵן גְּדֵלִים מִן הָאָרֶץ וְאֵין מְקַבְּלִין טֻמְאָה, וְאַף עַל פִּי שֶׁהֵן מְחֻבָּרִים26 – אֵין בְּכָךְ כְּלוּם, דְּתָלוּשׁ וּלְבַסּוֹף חִבְּרוֹ כָּשֵׁר לְסֻכָּהנה כְּמוֹ שֶׁיִּתְבָּאֵר בְּסִימָן תרכ"ט,נו,27 וְכֵיוָן שֶׁהֵן עַצְמָן כְּשֵׁרִים לִסְכָךְ עַל יְדֵי מַעֲשֶׂה זוֹ וְיָכוֹל לְהַנִּיחַ עֲלֵיהֶם עוֹד סְכָךְ כָּשֵׁר וְהֵן מִצְטָרְפִין עִם סְכָךְ זֶה לְהַשְׁלִים לְשִׁעוּר צִלָּתָהּ מְרֻבָּה מֵחַמָּתָהּ, וְלָכֵן גַּם עַכְשָׁו שֶׁלֹּא הִנִּיחַ הַסְּכָךְ עֲלֵיהֶם אֶלָּא תַּחְתֵּיהֶן לְמַטָּה בַּבַּיִת – מֻתָּר לֵישֵׁב תַּחְתֵּיהֶן מַמָּשׁ, כֵּיוָן שֶׁהֵם סְכָךְ כָּשֵׁר:נז

13 [Different rules apply,] however, if one did not remove the shingles for the sake of making a sukkah there, but the structure was initially built [with beams, though] without a roof. Since [in such a case] no action was taken with [the beams of] the roof for the sake of making a sukkah for shade, the wood or the beams are invalid as s’chach, and hence are governed by the laws that apply when invalid material covers valid s’chach, as explained [above].28 (I.e., whenever the valid s’chach is not so ample that if one removed an amount equivalent to the invalid material that casts a shadow over it, the shade [within the sukkah] would [still] exceed its sunlit area, [the sukkah] is invalid.)

יג אֲבָל אִם לֹא הֵסִיר אֶת הָרְעָפִים כְּדֵי לַעֲשׂוֹת שָׁם סֻכָּה אֶלָּא כָּךְ הָיְתָה מִקֹּדֶם בְּנוּיָה בְּלֹא גַּג, כֵּיוָן שֶׁלֹּא עָשָׂה שׁוּם מַעֲשֶׂה בַּגָּג לְשֵׁם עֲשִׂיַּת סֻכָּה לְצֵל, אִם כֵּן הָעֵצִים אוֹ הַקּוֹרוֹת הֵן סְכָךְ פָּסוּל, וְדִינוֹ כְּדִין סְכָךְ פָּסוּל הַמַּאֲהִיל עַל גַּבֵּי הַסְּכָךְ כָּשֵׁרנח וְעַל דֶּרֶךְ שֶׁנִּתְבָּאֵרנט,28 (פֵּרוּשׁ שֶׁכָּל שֶׁאֵין סְכָךְ הַכָּשֵׁר הַרְבֵּה כָּל כָּךְ עַד שֶׁאִם יִנָּטֵל מִמֶּנּוּ כְּשִׁעוּר סְכָךְ הַפָּסוּל הַמֵּצֵל עָלָיו יִהְיֶה עֲדַיִן צֵל הַסֻּכָּה מְרֻבֶּה מֵחַמָּתָהּ – פָּסוּלס):

14 When does the above apply? When the s’chach was placed below [the exposed frame of] the roof. If, however, the s’chach was placed upon the wood or the beams, then even if there was less than three handbreadths’ space between [the beams], [the sukkah] is valid.

We do not apply the principle of lavud29 and regard all the pieces of wood as joined, and thus they would be considered as one piece of wood that was invalid as s’chach and wider than four handbreadths, and hence would disqualify the sukkah, as will be explained in sec. 632.30 The reason [we do not follow this principle] is that the valid s’chach that is placed between one piece of wood and another disrupts their [halachic] continuity. The principle of lavud can apply only when nothing interposes between the neighboring entities.

יד בַּמֶּה דְּבָרִים אֲמוּרִים? כְּשֶׁמְּסַכֵּךְ תַּחַת הַגָּג, אֲבָל אִם מְסַכֵּךְ עַל גַּבֵּי הָעֵצִים אוֹ הַקּוֹרוֹת, אַף עַל פִּי שֶׁהֵן סְמוּכִין זֶה לָזֶה בְּפָחוֹת מִשְּׁלֹשָׁה טְפָחִים – הֲרֵי זוֹ כְּשֵׁרָה, וְאֵין אוֹמְרִים כָּאן לָבוּד29 שֶׁיִּצְטָרְפוּ כָּל הָעֵצִים וְיִהְיוּ נֶחְשָׁבִין כְּעֵץ אֶחָד רָחָב מִסְּכָךְ הַפָּסוּל יוֹתֵר מֵאַרְבָּעָה טְפָחִים שֶׁהוּא פּוֹסֵל אֶת הַסֻּכָּה כְּמוֹ שֶׁיִּתְבָּאֵר בְּסִימָן תרל"ב,סא,30 שֶׁכֵּיוָן שֶׁסְּכָךְ כָּשֵׁר מֻנָּח בֵּין עֵץ לַחֲבֵירוֹ – הוּא מַפְסִיק בֵּינֵיהֶם שֶׁלֹּא יִצְטָרְפוּ,סב וְאֵין אוֹמְרִים לָבוּד אֶלָּא אִם כֵּן אֵין שׁוּם דָּבָר מַפְסִיק בֵּינְתַיִם:

15 [The question of] whether [or not] it is permissible to sit under the wood is explained in sec. 631.31

טו וְאִם מֻתָּר לֵישֵׁב תַּחַת הָעֵצִים – יִתְבָּאֵר בְּסִימָן תרל"א:סג,31

16 [One halachic principle applies in both of the following situations. A person first] placed material that is invalid as s’chach on a sukkah that had no s’chach. He then placed valid s’chach above the invalid material. Finally, he removed the invalid material, leaving only the upper, valid s’chach casting shade on the [floor of the] sukkah. Similarly, a person built the walls of the sukkah below the roof of his house, placed valid s’chach above the roof, and then removed the roof that was under the s’chach. [In both instances, the sukkah] is invalid, because at the time he made the sukkah — i.e., at the time he put the valid s’chach in place, which is the essence of [making] the sukkah — the sukkah was invalid because of the invalid material that covered it [directly]. Afterwards, when he removed this invalid material, he did not perform an act involving the sukkah itself32 to make it acceptable; it was validated [so to speak] as a matter of course, by the removal of the invalid material.

The Torah, however, states,33 “Make the Sukkos festival for yourself.” [Implied is that the sukkah must be made.] We may not [use] something which is already made, [but which later became suitable] as a matter of course34 — for the initial act of making, which was invalid, is not considered “making” at all.35

טז אִם הִנִּיחַ סְכָךְ פָּסוּל עַל גַּבֵּי הַסֻּכָּה שֶׁלֹּא הָיָה עָלֶיהָ שׁוּם סְכָךְ וְאַחַר כָּךְ הִנִּיחַ עָלֶיהָ סְכָךְ כָּשֵׁר עַל גַּבֵּי סְכָךְ הַפָּסוּל וְאַחַר כָּךְ הֵסִיר סְכָךְ הַפָּסוּל מֵעַל גַּבֵּי הַסֻּכָּה וְנִשְׁאַר סְכָךְ הָעֶלְיוֹן הַכָּשֵׁר בִּלְבַדּוֹ מֵצֵל עַל גַּבֵּי הַסֻּכָּה, וְכֵן הָעוֹשֶׂה דָּפְנוֹת הַסֻּכָּה תַּחַת גַּג הַבַּיִת וְהִנִּיחַ סְכָךְ כָּשֵׁר עַל גַּבֵּי הַגָּג וְאַחַר כָּךְ הֵסִיר אֶת הַגָּג מִתַּחַת הַסְּכָךְ הַמֻּנָּח עָלֶיהָ – הֲרֵי זוֹ פְּסוּלָה,סד לְפִי שֶׁבְּשָׁעָה שֶׁעָשָׂה אֶת הַסֻּכָּה, דְּהַיְנוּ בְּשָׁעָה שֶׁהִנִּיחַ סְכָךְ הַכָּשֵׁר שֶׁהוּא עִקַּר הַסֻּכָּה, הָיְתָה הַסֻּכָּה פְּסוּלָה מֵחֲמַת סְכָךְ הַפָּסוּל שֶׁעָלֶיהָ, וְאַחַר כָּךְ כְּשֶׁהֵסִיר אֶת הַפָּסוּל לֹא עָשָׂה מַעֲשֶׂה בְּגוּף הַסֻּכָּה32 לְהַכְשִׁירָהּ אֶלָּא מֵאֵלֶיהָ נִתְכַּשְּׁרָה עַל יְדֵי הֲסָרַת הַפְּסוּל, וְהַתּוֹרָה אָמְרָהסה,33 "חַג הַסֻּכּוֹת תַּעֲשֶׂה לְךָ וגו'", וְלֹא מִן הֶעָשׂוּיסו מֵאֵלָיו,סז,34 שֶׁהָעֲשִׂיָּה הָרִאשׁוֹנָה שֶׁהָיְתָה בִּפְסוּל – אֵינָהּ נֶחְשֶׁבֶת עֲשִׂיָּה כְּלָל:,35

17 When does the above apply? When the disqualifying factor was inherent in the sukkah; for example, in the instance above when valid s’chach was placed over invalid material. In this instance, the sukkah itself — i.e., [what should have been] the valid s’chach — was made in an inherently invalid manner. It could not be called s’chach at all, because some other entity interposed between it and the walls, and [thus] the shade it produces is of no consequence whatever.36

If, however, [the s’chach] is disqualified by an external factor — e.g., one constructed his sukkah under the roof of a house and, after placing s’chach upon it as required by law, removed the roof [of the house] that was above the sukkah — it is valid, even though no action was taken with [the s’chach] itself to make it valid. [The rationale is that] it was disqualified only by an external factor, namely, the roof of the house that cast shade over it; it is not inherently invalid. [On the contrary, the sukkah] was covered as required by law, with valid s’chach placed over its walls. Hence, [the sukkah] becomes valid when this was brought about by a validating action taken with the disqualifying factor; i.e., one removed the wooden pieces of the roof that had been affixed there to create a dwelling and not to generate shade, and hence had been deemed invalid as s’chach. When, however, they have been entirely removed from there, [the s’chach of the sukkah]37 — so, too, even the remaining beams — is now also considered as valid s’chach, as explained [in subsection 12] above. The action is effective in rendering the sukkah valid, because it had been disqualified only by the roof, and something was [since] done to [the roof] to rectify that factor.

יז בַּמֶּה דְּבָרִים אֲמוּרִים? שֶׁפְּסוּל הַסֻּכָּה הָיָה מֵחֲמַת עַצְמָהּ, כְּגוֹן בְּנִדּוֹן שֶׁאָמַרְנוּ שֶׁהִנִּיחַ סְכָךְ הַכָּשֵׁר עַל גַּבֵּי הַפָּסוּל, שֶׁגּוּף הַסֻּכָּה דְּהַיְנוּ סְכָךְ הַכָּשֵׁר נַעֲשָׂה בִּפְסוּל מֵחֲמַת עַצְמוֹ, שֶׁאֵינוֹ נִקְרָא סְכָךְ כְּלָל כֵּיוָן שֶׁיֵּשׁ דָּבָר מַפְסִיק בֵּינוֹ לְהַדְּפָנוֹת, שֶׁהֲרֵי אֵין צִלּוֹ מוֹעִיל כְּלוּם.סח,36

אֲבָל אִם פְּסוּל הַסֻּכָּה הוּא מֵחֲמַת דָּבָר אַחֵר הַפּוֹסֵל אוֹתָהּ, כְּגוֹן הָעוֹשֶׂה סֻכָּתוֹ תַּחַת גַּג הַבַּיִת וְאַחַר שֶׁסִּכְּכָהּ כְּהִלְכָתָהּ הֵסִיר אֶת הַגָּג מֵעַל גַּבֵּי הַסֻּכָּה – הֲרֵי זוֹ כְּשֵׁרָהסט אַף עַל פִּי שֶׁלֹּא עָשָׂה מַעֲשֶׂה בְּגוּפָהּ לְהַכְשִׁירָהּ, כֵּיוָן שֶׁאֵין פְּסוּלָה אֶלָּא מֵחֲמַת דָּבָר אַחֵר דְּהַיְנוּ גַּג הַבַּיִת שֶׁמֵּצֵל עָלָיו וְלֹא מֵחֲמַת עַצְמָהּ, שֶׁהֲרֵי הִיא מְסֻכֶּכֶת כְּהִלְכָתָהּ בִּסְכָךְ כָּשֵׁרע הַמֻּנָּח עַל גַּבֵּי דָּפְנוֹתֶיהָ, לְכָךְ כֵּיוָן שֶׁעָשָׂה מַעֲשֶׂה הַכָּשֵׁר בְּדָבָר הַפּוֹסְלָהּ,עא דְּהַיְנוּ שֶׁהֵסִיר אֶת עֲצֵי הַגָּג שֶׁהָיוּ קְבוּעִין שָׁם לְשֵׁם דִּירָה וְלֹא לְשֵׁם צֵל, וּלְפִיכָךְ הָיָה עָלֶיהָ שֵׁם סְכָךְ פָּסוּל, וְעַכְשָׁו שֶׁהֱסִירָן מִשָּׁם לְגַמְרֵי37 – נִקְרָא עֲלֵיהֶם שֵׁם סְכָךְ כָּשֵׁר, וַאֲפִלּוּ עַל הָעֵצִים הַנִּשְׁאָרִים נִקְרָא עֲלֵיהֶם שֵׁם סְכָךְ כָּשֵׁר כְּמוֹ שֶׁבֵּאַרְנוּ לְמַעְלָה,עב לְפִיכָךְ מוֹעִיל מַעֲשֶׂה הַכָּשֵׁר זֶה לְהַכְשִׁיר אֶת הַסֻּכָּה, כֵּיוָן שֶׁלֹּא הָיְתָה פְּסוּלָה אֶלָּא מֵחֲמַת הַגָּג וּכְבָר עָשָׂה בּוֹ מַעֲשֶׂה הַכָּשֵׁר:

18 [Different rules apply] if one did not perform an action to validate the sukkah [by changing] the disqualifying factor itself; e.g., he did not remove the roof entirely from the place where it was fixed, but [placed it on hinges, so that] it served as a door, to be opened and closed during the rain.

In such a situation, since the roof was not removed entirely, the above action is not sufficient to validate the remaining [supporting] beams and the [s’chach] which was disqualified because of it ([and which was already in place] when the hinged roof38 was not yet opened, but overhung the sukkah).

יח אֲבָל אִם לֹא עָשָׂה מַעֲשֶׂה הַכָּשֵׁר בְּדָבָר הַפּוֹסְלָהּ, כְּגוֹן שֶׁלֹּא הֵסִיר אֶת הַגָּג לְגַמְרֵי מִמְּקוֹם קְבִיעוּתוֹ, אֶלָּא עָשָׂה אוֹתוֹ כְּעֵין דֶּלֶת לִפְתֹּחַ וְלִסְגֹּר בְּעֵת הַגֶּשֶׁם, כֵּיוָן שֶׁלֹּא הֱסִירוֹ מִשָּׁם לְגַמְרֵי – אֵין זֶה מַעֲשֶׂהעג גָּמוּר, וּלְפִיכָךְ אֵינוֹ מוֹעִיל לְהַכְשִׁיר אֶת הָעֵצִים הַנִּשְׁאָרִים וְלֹא אֶת הַסֻּכָּה שֶׁנִּפְסְלָה מֵחַמָּתָהּ (כְּשֶׁעֲדַיִן לֹא נִפְתְּחָה הַדֶּלֶת וְהָיְתָה מַאֲהֶלֶת עַל הַסֻּכָּה):

19 When is [the sukkah disqualified] because of this? When the s’chach was placed on the sukkah before he made an opening for the hinged cover38 in the roof — or even after [that opening] was made, except that when the s’chach was put in place, the hinged cover38 was closed and overhung the sukkah. Since the sukkah was constructed [i.e., since the s’chach was put in place] invalidly, the fact that the hinged cover was later opened is not sufficient to render it valid, for no action was taken [to change] the sukkah itself.

If, however, at the time one covered the sukkah with s’chach, the hinged roof was open as required by law and did not overhang it, [the sukkah is valid]. Even if it is later closed, and thus the sukkah was disqualified while the hinged roof was closed, the sukkah becomes valid again when the hinged roof is opened. For the sukkah was initially made [i.e., the s’chach was put in place] validly, since the door was then open.39

יט בַּמֶּה דְּבָרִים אֲמוּרִים? כְּשֶׁסִּכֵּךְ אֶת הַסֻּכָּה קֹדֶם שֶׁפָּתַח אֶת הַדֶּלֶת38 בַּגָּג, אוֹ אֲפִלּוּ לְאַחַר שֶׁפָּתַח אֶלָּא שֶׁבִּשְׁעַת הַסִּכּוּךְ הָיְתָה הַדֶּלֶת38 סְגוּרָה וְהָיְתָה מַאֲהֶלֶת עַל הַסֻּכָּה, דְּכֵיוָן שֶׁעֲשִׂיַּת הַסֻּכָּה הָיְתָה בִּפְסוּל – שׁוּב אֵין מוֹעִיל לָהּ מַה שֶּׁאַחַר כָּךְ פָּתַח אֶת הַדֶּלֶת, כֵּיוָן שֶׁלֹּא עָשָׂה מַעֲשֶׂה בְּגוּף הַסֻּכָּה. אֲבָל אִם בְּשָׁעָה שֶׁסִּיכְּכָהּ הָיְתָה הַדֶּלֶת פְּתוּחָה כְּהִלְכָתָהּ וְלֹא הָיְתָה מַאֲהֶלֶת עַל הַסֻּכָּה, אַף עַל פִּי שֶׁאַחַר כָּךְ סְגָרָהּ וְנִפְסְלָה הַסֻּכָּה בְּשָׁעָה שֶׁהַדֶּלֶת סְגוּרָה, מִכָּל מָקוֹם כְּשֶׁהוּא פּוֹתֵחַ אֶת הַדֶּלֶת – הַסֻּכָּה חוֹזֶרֶת לְהֶכְשֵׁרָהּ, כֵּיוָן שֶׁתְּחִלַּת עֲשִׂיָּתָהּ הָיְתָה בְּכַשְׁרוּת בְּשָׁעָה שֶׁהַדֶּלֶת הָיְתָה פְּתוּחָה:עד,39

20 If this [retractable roof]38 has hinges that enable it to be opened and closed, it completely fits the halachic definition of an entrance and may be closed and opened on Shabbos and the festivals. [Doing so] does not involve the forbidden [labors] of demolishing or building.40

כ וְאִם יֵשׁ לְדֶלֶת זוֹ38 צִירִים שֶׁסּוֹגֵר וּפוֹתֵחַ בָּהֶםעה – הֲרֵי הִיא כְּפֶתַחעו גָּמוּר, וּמֻתָּר לְסָגְרָהּ וּלְפָתְחָהּ בְּשַׁבָּת וְיוֹם טוֹב, וְאֵין בָּזֶה מִשּׁוּם אִסּוּר סְתִירָה וּבִנְיָן:עז,40

21 When [the hinged roof] is closed, one must be careful not to sit under it with the intent of fulfilling the mitzvah of the sukkah, for at that time the sukkah is not valid and one does not fulfill his obligation by dwelling in it.

כא וְצָרִיךְ שֶׁיִּזָּהֵר שֶׁלֹּא יֵשֵׁב תַּחְתֶּיהָ לְשֵׁם מִצְוַת סֻכָּה כְּשֶׁהִיא סְגוּרָה, שֶׁאָז הִיא פְּסוּלָה,עח וְאֵינוֹ יוֹצֵא יְדֵי חוֹבָתוֹ בִּישִׁיבָה זוֹ: