Doorpost only behind the Door

Question:

We recently married off our youngest son and have moved from our family home into an apartment. I mentioned to my new neighbor that I was surprised to see that seemingly none of the Jewish families had put mezuzot on their doors. He told me that their mezuzot were on the doorposts behind their doors. He explained that since the front doors were flush with the wall, and the only place to put a mezuzah was on the outside of the frame, they had acted correctly. I am proud of my Jewish identity and would like to display my mezuzah on the outside. Am I allowed?

Answer:

You are correct that ideally the mezuzah should be placed outside the door so that one encounters it upon entrance and also to ensure that the whole dwelling is protected. Your desire to proudly display your mezuzah is also commendable.

However, since, in your case, the mezuzah would thus not be within the doorframe and under its lintel, it is questionable whether its placement would fulfill the Torah’s command. Your neighbors have done correctly, as the entire doorframe — even the part behind the door — is acceptable for mezuzah placement.[1] This is true even if the mezuzah is obscured by the door when it is open.[2]^[A]

When there is absolutely no room on the inside of the doorway for the mezuzah, it may be placed on the outer frame without a berachah. [3]^[B]

Alternatively, if you owned the apartment, you could dig out a shallow indentation[4] in the doorframe and place the mezuzah there.^[C]

[See also question “No Space at All on Post.”]

[1] Agur B’ohalecha 14:2.

[2] Mezuzot Beitecha 289:8; Chovas HaDar 8:2.

[3] Mezuzot Beitecha 289:8. No berachah is recited when one is forced to place the mezuzah on the outer frame, not under the lintel.

[4] Less than eight cm. deep. (?)

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