halacha - Halachot of Shul Mechitzot

What are some good books, articles, websites, or seforim for learning about the Halachot of constructing and maintaining a Shul Mechitza (the barrier between the men and women sections)?

Issues include: How tall and wide must they be? Can there be any gaps between the sections? Must they completely opaque on both sides, or can they be one-sided mirrors and the like? Do they have to be permanent? Etc. Appreciated, but not required: What's the history of the Mechitza?

I'd appreciate materials that are well sourced and\or footnoted, in either English or Hebrew. Thanks you.

Answer

Rabbi J.H. Henkin has an excellent essay, going from the Talmudic sources to his interpretation of modern-day requirements. I strongly recommend you start there. (Link is to Google Books; many good libraries have this book in English. I believe this essay is based on material he's previously published in She'elot UTeshuvot Bnei Banim, which is available as pdf on hebrewbooks.org.

Here's one organization's roundup of sources.

But on one foot:

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  How tall? See Henkin's essay for the technical height requirements. For America in the 1960s and 1970s, Rabbi Moshe Feinstein recommended 5 feet; that way if a woman showed up at synagogue "with bared arms ... and more", all that's visible (for an average-height woman) from the men's side is from the neck up, so prayers can still be said.

  
  


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  Width, gaps -- see Henkin's essay. Depends what exact requirements it must meet.

  
  
  


• Opacity: some, including Rabbi Yoel Teitelbaum of Satmar, insisted that a feature of a mechitza be opaque, that men shall not see the women. As I understand it, Rabbi Moshe Feinstein felt that a glass mechitza would have met all requirements, so long as the women dressed appropriately. (As often they didn't, he advised five feet of opacity.)


• Permanance: again, see Henkin (though many a synagogue does use a hanging curtain). Another question is whether any prayer service requires one, or only a fixed service, open to the public. More here.


• History: Talmud says they had to add a women's section in the Temple because of excess levity. As I understand it, archeological excavations of synagogues back to easily 1700 years ago have always found a mechitza of some sort.