א סְכָךְ פָּסוּל, פּוֹסֵל בָּאֶמְצַע בְּד' טְפָחִים; אֲבָל פָּחוֹת מִד', כְּשֵׁרָה, וּמֻתָּר לִישַׁן תַּחְתָּיו מִן הַצַּד אֵינוֹ פּוֹסֵל אֶלָּא בְּד' אַמּוֹת, אֲבָל פָּחוֹת מִד' אַמּוֹת, כְּשֵׁרָה דְּאָמְרִינָן דֹּפֶן עֲקֻמָּה, דְּהַיְנוּ לוֹמַר שֶׁאָנוּ רוֹאִים כְּאִלּוּ הַכֹּתֶל נֶעֱקָם וְיֵחָשֵׁב זֶה הַסְכָךְ הַפָּסוּל מִגּוּף הַכֹּתֶל, וְדָבָר זֶה הֲלָכָה לְמֹשֶׁה מִסִינַי. הִילְכָּךְ בַּיִת שֶׁנִּפְחַת בָּאֶמְצַע וְסִכֵּךְ בִּמְקוֹם הַפְּחָת וְנִשְׁאַר מִן הַתִּקְרָה סָבִיב בֵּין סְכָךְ כָּשֵׁר לַכְּתָלִים פָּחוֹת מֵאַרְבַּע אַמּוֹת, כְּשֵׁרָה, וּמִיהוּ אֵין יְשֵׁנִים תַּחְתָּיו כָּל זְמַן שֶׁיֵּשׁ בּוֹ אַרְבָּעָה טְפָחִים. בַּמֶּה דְּבָרִים אֲמוּרִים, בְּסֻכָּה גְּדוֹלָה שֶׁיֵּשׁ בָּהּ יוֹתֵר עַל הַסְכָךְ פָּסוּל ז' טְפָחִים עַל ז' טְפָחִים; אֲבָל בְּסֻכָּה קְטַנָּה, שֶׁאֵין בָּהּ אֶלָּא ז' עַל ז', בֵּין בָּאֶמְצַע בֵּין מִן הַצַּד, בְּג' טְפָחִים פְּסוּלָה, בְּפָחוֹת מִג' כְּשֵׁרָה וִישֵׁנִים תַּחְתָּיו וּמִצְטָרֵף לְהַשְׁלִים הַסֻכָּה לְכַשִּׁעוּר.
1 Things That Are Invalid For S'chach, having four Seifim: Invalid s'chach, makes a sukkah invalid in the middle if it is four tefachim. However, less than 4 is valid and one is permitted to sleep under it. From the side, it does not invalidate except if the invalid s'chach measures 4 amot, but less than 4 it is valid, for we say it is a curved wall; for we could say that we see it as if the wall is bent, and we consider this invalid s'chach to be from the body of the wall. This is a law given to Moshe at Sinai. Therefore, for this reason, a house which is reduced in the middle and one covers the middle area with s'chach, and there remains from the ceiling around the valid s'chach less than 4 amot between it and the walls, it is valid. However, we do not sleep underneath it whenever it measures 4 tefachim. With regard to what have these things been said? With regard to a large sukkah that has, in addition to the invalid s'chach, more than 7 x 7 tefachim. However, in a small sukkah which only has 7 x 7, whether in the middle or on the side, when there are three tefachim, it is invalid. When there are less than three tefachim, it is a valid sukkah and we may sleep underneath it and it joins together to complete the measure of the sukkah.