Sukkah 11A

ובית נמי, אף על פי שאין גבוה עשרה, כיון דקביע ⁠— אוהלא הוא, דלא גרע מקינופות.

And this halakha that it is not sufficient to place his head out the window applies also to a house even if it is not 10 handbreadths high. Since it is a fixed structure it is considered a tent in and of itself, as it is no less permanent than a bed with 4 posts, which is considered a tent even though the netting is less than 10 handbreadths higher than the bed.

לישנא אחרינא אמרי לה, אמר רב יהודה אמר שמואל: מותר לישן בכילת חתנים בסוכה לפי שאין לה גג, אף על פי שגבוהה עשרה.

Some say another version of the previous discussion: Rav Yehuda said that Shmuel said: It is permitted to sleep inside a netted bridal canopy in the sukka since it is inclined and does not have a roof, even though it is 10 handbreadths high.

מיתיבי: הישן בכילה בסוכה ⁠— לא יצא ידי חובתו! הכא במאי עסקינן ⁠— בשיש לה גג.

The Talmud raises an objection from a baraita: One who sleeps in a bed with netting inside the sukka did not fulfill his obligation. The Talmud answers: With what are we dealing here in the baraita? It is with a bed with netting in a case where, unlike a bridal canopy, it has a roof.

תא שמע: נקליטין שנים, וקינופות ארבעה, פירס על גבי קינופות ⁠— פסולה, על גבי נקליטין ⁠— כשרה, ובלבד שלא יהו נקליטין גבוהין מן המטה עשרה טפחים. הא גבוהין מן המטה עשרה ⁠— פסולה, אף על פי שאין לה גג!

Come and hear another question from what we learned: Naklitin are two posts and kinofot are 4 posts. If one spread a sheet over 4 posts, the sukka is unfit; if he spread a sheet over two posts the sukka is fit, provided the two posts are not 10 handbreadths higher than the bed. It can be inferred from here: But if they are higher than 10 handbreadths the sukka is unfit even though it has no roof, contrary to the opinion of Shmuel.