Daf HaYomi B'Halacha Daily Email - 8 Teves/Dec 12

What is the preferred height of the menorah? The lights of the menorah must be at least three tefachim from the ground. B’dieved, one is still yotzei if they are lower than three tefachim. Preferably, they should not be higher than ten tefachim. A menorah may not be placed higher than twenty amos from the ground. People’s eyes do not focus well on objects at such a height, so the menorah would be missing the necessary component of pirsumei nisa. The poskim disagree about whether one may light by a window that is more than twenty amos high but faces other buildings. [ Shu'a Tira'a, 6, and Mishnav Kaach; Annotations and Supplements Required, 56 ]

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