Ask the Rov: Does a walk-in closet need a mezuzah?

By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah

The mitzva of mezuzah applies to each doorway in one’s home that leads to a room used for dwelling (“bayis”). One of the criteria for this halachic status is a minimum area of four-by-four amos, which the Rosh explains as a square of four-by-four.

The Rambam adds the obligation applies even if the room is rectangular or round, and this is quoted in Shulchan Aruch.¹ Some understand the Rambam to include rooms of other proportions, even if narrower than four amos, provided the total area equals 16 square amos (e.g., a rectangle of two by six amos, so long as it’s one area, not projections or L-shaped extensions).²

However, others question this understanding of the Rambam, explaining that all he meant was that the room need not be a perfect square, as long as it can hold a square of four-by-four amos.³ In Hilchos Eruvin, the Alter Rebbe rules that an actual square of four-by-four amos is necessary (and refers to Hilchos Mezuzah).⁴

Usable shelf space is included in the measured area, but unusable space taken up by a furnace or boiler, for instance, needn’t be counted.⁵

While the Shulchan Aruch exempts rooms smaller than the shiur, some acharonim argue this applies only to lived-in rooms that aren’t functional below minimum size. Closets, however, serve their purpose regardless of size and remain obligated.⁶

Rabbi Akiva Eiger argues that while the entrance to a small walk-in closet is exempt, it is nevertheless obligated as an entrance back into the bedroom. Thus, he rules, a mezuzah should be placed on the right side going from the closet to the room.⁷

In practice, one is not obligated to place a mezuzah on a walk-in closet less than the shiur, yet there is room to be mehader to place one on the right side exiting the closet.⁸

Even the hiddur applies only when normal use requires fully entering the room. But if the closet’s use involves only reaching in, it’s definitely not considered an “entrance” (even if one occasionally enters to clean or retrieve dropped items).

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From The Weekly Farbrengen by Merkaz Anash