Genesis 33:17

ויבן לו בית AND HE BUILT FOR HIMSELF A HOUSE — He stayed there eighteen months — summer, winter and summer again (Megillah 17a); for the first mention of Succoth (booths which are erected for the cattle) points to the summer (when booths are necessary for the cattle), the mention of building a house to the winter, and the second mention of booths to the next summer.

וְיַעֲקֹב֙ נָסַ֣ע סֻכֹּ֔תָה וַיִּ֥בֶן ל֖וֹ בָּ֑יִת וּלְמִקְנֵ֙הוּ֙ עָשָׂ֣ה סֻכֹּ֔ת עַל־כֵּ֛ן קָרָ֥א שֵׁם־הַמָּק֖וֹם סֻכּֽוֹת׃ {ס}        

And Ya῾aqov journeyed to Sukkot, and built him a house, and made booths for his cattle: therefore the name of the place is called Sukkot.