Ideally, the ner Chanuka should be placed between three and ten tefachim off the ground. If it was placed between ten tefachim and twenty amos, the mitzva has been fulfilled. If it was placed above twenty amos, however, the obligation is not fulfilled. People passing by would not easily notice the burning candles at such a height, and the criterion of persumei nissa is thus not met. According to Rav Shlomo Zalman, in a cluster of tall apartment buildings it is preferable for the residents of the upper floors to put their menoros in the doorway leading to the hall (or stairwell) rather than in the window. The residents of the nearby buildings who can see the candles do not play the same role as passersby on the street. Rav Nissim Karelitz adds that in this instance, the menorah should be placed in a way that it is visible to those inside the apartment as well as those outside. According to Rav Sheinberg, the menorah should be put in the window because the persumei nisa effect will be greater there. Rav Wosner advises that since there is minimal persumei nisa to those on the street at the same time as some persumei nisa to the surrounding buildings, the custom of lighting in the window should be upheld.

[ שו"ע תרעא, ו, ומשנ"ב כח; ביאורים ומוספים 'דרשו', 56 ]