“Question: Are married women obligated to cover their hair in the confines of their own home (in private)?
Discussion: We find a major dispute among the Rishonim and Acharonim about this very point:
According to Rashi (Kesubos 72b, quoted in the Beis Shmuel Even Ho’ezer Siman 115 s.k. 9) and Tosfos (Kesubos ibid, quoted in the Beis Shmuel ibid) there is no requirement for a married lady to cover her hair in the confines of her private courtyard [where she will not be seen by others; all the more so inside of her house].
The Magen Avraham (Siman 75 s.k. 4) quotes the aforementioned Tosfos, and then quotes the Zohar (Parshas Naso page 239) who writes that no hair of a lady should be seen [which implies even in private]. The Magen Avraham concludes that it is fitting to act as per the Zohar [and a married lady should indeed cover her hair even in private]. It appears that the Magen Avraham posits that although according to the letter of the law it is permitted for a married lady to expose her hair even in the confines of her private courtyard, it is highly unadvisable to do so (based on the Zohar).
However, the view of the Sma”g (Mitzvos Aseh 48), the Shiltei Giborim (Kesubos 32), Bach (Even Ho’ezer Siman 115 s.k. 3) and Chasam Sofer (Responsa Orach Chayim Siman 36) is that a [married] lady is forbidden to completely expose her hair even in the confines of her own private courtyard.
[Even according to the stringent opinions, it is of course permitted for a lady to expose her hair when there is a need to do so, for example while she is washing (Rav Eliyohu Falk in Oz v’Hodor Levusha Perek 5).]
The Bi’ur Halocho (Siman 75 d.h. “chutz”) quotes the aforementioned Magen Avraham and comments that this lenient view is not unanimous, since many of the Poskim rule stringently. The Bi’ur Halocho refrains from giving a clear ruling on the topic, but it appears from context that he favours the stringent opinion.
The Bi’ur Halocho also adds that there is another potential issue over here, and that is the prohibition of other saying d’vorim shebikdusha in view of her uncovered hair:
The Shulchan Aruch (Orach Chayim Siman 75 se’if 2) rules that it is forbidden to recite keriyas shema while facing the hair of a married lady. The Remo (ibid) adds that this even applies to one’s wife.
Therefore, even according to the lenient opinions who maintain that a lady does not need to cover her hair in the confines of her home, uncovered hair poses a major issue to others who recite brochos in view of her uncovered hair.
Conclusion: Whether or not a married lady is obligated to cover her hair in the confines of her own home (where others will not see her) is a major dispute among the Poskim. In any event, the Zohar expounds on the tremendous benefits of ladies covering their hair, and of the negative consequences of those who do not do so. Additionally, the Bi’ur Halocho emphasizes that uncovered hair poses a serious issue for others who wish to recite d’vorim shebikdusha in view of a married lady’s uncovered hair (this applies even to her husband and other immediate family members). Therefore, although there are lenient authorities and therefore we cannot mandate married ladies to cover their hair in the confines of their own houses, since many authorities rule stringently it is highly recommended for married ladies to cover their hair even in the confines of their own houses and should be encouraged wherever and whenever possible.
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