580. More About the Intermittent Doorway

In an introductory note to this chapter, the Kitzur Shulchan Aruch writes that most Jews are already familiar with the prohibited labors of Shabbos and that he is only addressing common situations with which people may not be familiar. Clearly, the laws of Shabbos constitute an area requiring much greater study than this email alone will allow. 80:69 If the door (used to cover an opening used only intermittently as an entrance – see yesterday’s halachos) is not attached to and hanging in the doorway, and one must completely remove it in order to open it, then we may not use it to close an opening that isn’t used regularly to enter and exit. If the opening is designed for regular use as an entrance and exit, then we may close it with such a door on Shabbos even if it doesn't have a mark indicating where there used to be a hinge.

80:70 A door made of a single board may not be used to close an entrance that's not regularly used, even if it has a hinge. If it doesn't actually swing on its hinges, because it’s just a single board that doesn't swing, it resembles an act of construction to cover a breach. However, when it comes to an opening that was designed for regular use as an entrance, we may be lenient about closing it with such a door so long as the opening has a doorframe, making it obvious that this is an entrance.