Kedushas bais haknesses is not attributed to places where people daaven irregularly. (ShA 1)
Kedushas bais haknesses is not attributed to a person’s living quarters even if a minyan daavens there all the time – since it is not designated solely for tefilla. (MB 2)
Spaces outside of the shul that late comers use for overflow whenever there is a crowd, have kedushas bais haknesses. Shul courtyards that are in the big cities certainly have kedusha since they are used for minyonim all of the time. (MB 3)
A premises that is rented out to a shul has kedusha for the duration of the contract. (BeH “hasochrim”)
Tashmishay kedusha are to give honour to kedusha and therefore have holiness. You may not use them for mundane purposes and when worn out they mustn’t be thrown away – put them into geniza. (MB 6, 9)
Something that serves only the tashmish kedusha has no kedusha at all. (MB 6)
Examples of tashmishay kedusha: A case for a book of Tanach, a mezuzah case, tefillin straps, tefillin bag, the desk for krias haTorah (when the sefer Torah sometimes rests directly on it), the cloth cover on the desk for krias haTorah, silver breastplates that hang upon the sefer Torah. (ShA 3 – MB 7,9,10 – ShaH 7)
Anything that comes into direct contact with kedusha is tashmish kedusha even if only to protect the kedusha (e.g. belt around the sefer Torah). (BeH “v’davka”)
Rotting particles that fall off of sefarim and Torah covers have kedusha and must be disposed of into geniza. (MB12)
A free standing Aron Kodesh is tashmish kedusha. The inner lining or paneling of a built-in Aron Kodesh has a status of tashmish kedusha. (Rama 3 – MB 16)
Any worn out scroll of Tanach must be placed in an earthenware container and buried in the grave of a talmid chochom. But, I haven’t seen this conduct performed. (ShA 5 – MB 22 – BeH “v’gonzin”)
One who destroys kisvay hakodesh transgresses a negative commandment. This applies also to tashmishay kedusha. Do not get rid of such worn out objects by burning them. (MB 24)
The paroches has only kedushas bais haknesses, not tashmishay kedusha. (Rama 6).
The yad (pointer) is hung to decorate the sefer Torah, it has a din of tashmishay kedusha. (MB 31)
You are allowed to keep possul sifray Torah in an Aron Kodesh, but no other sefarim, even temporarily. (MB 31)
A temporary Aron Kodesh loses its kedusha when you begin to use the permanent one. (MB 31)
You maynot use a sefer for your own purposes. Examples: to shield the sunlight, to block your friend’s view, as a folder for writing-paper, to test a pen to see if it writes, to jot down an equation. (MB 31)
You may use a sefer to prop up another sefer that you are learning, or to block the sunlight shining on a sefer that you are learning if you need to. (MB 31)
You may use a sefer as a writing surface for paper that already has divray Torah written on it if you need to. Similarly you may keep such papers tucked into a sefer. (MB 31)
If you make a condition to limit the kedusha of tashmishay kedusha, it works to permit you to use them for mundane (not disgraceful) purposes. (ShA 8 – MB 34)
The above condition must be made at the beginning of its manufacture. This condition may also be made before buying or donating items to a shul. (MB 33, 37)
The minhag is to allow tashmishay kedusha to be used in mundane ways that are commonly done in shul. The reason given is that there is an automatic unspoken condition made on such items so that the public does not come to transgression. This is called “Lev Bais Din Masneh Alayhem”. (Rama 8 – MB 35)
This automatic condition helps only for such benefits that are customary. Do not be lenient to allow all kinds of benefit from the shul’s tashmishay kedusha. (MB 36)
If you are donating items to the shul, do not rely upon this automatic condition – verbalize the condition. The same applies to a trustee buying things to be used as tashmishay kedusha. (MB 37)
Something that has been used for avoda zora may not be used for any subsequent mitzva. For example: used candles from a temple may not be lit to learn Torah. (MB 45)
A temple that has idols inside is considered a tashmish avoda zora and may not be used by a Jew. If the gentiles remove the idols from the temple a bittul takes place. A Jew may now buy the building for personal use. It still remains disqualified for mitzva use and therefore may not be used as a shul. (MB 45)
A building can only become forbidden if it is owned by the temple. If it is only rented, there is room to be lenient. (BeH “nairos”)
A prayer hall with no idols in it, and itself is not worshiped, can be bought to be used as a shul. (MB 45)
The benches of a temple are not for beautification and do not become forbidden. They may be bought for use in a shul. (MB 46)
If you find a rodent in a container of oil and it disgusts you, do not use the oil for mitzva purposes. (ShA 12 – MB 50)
Candles at shul are not to be used to read mundane reading material. Since the flames have kedushas bais haknesses, they also may not be used to transfer their flame for a non-mitzva use. (ShA 13, 14 – MB 52,53)
If the candle is about to be extinguished, it has ceased its mitzva purpose and may now be used for non-mitzva purposes. (ShA 14)
You are allowed to light up a pipe from a 24-hour yohrzeit light. (MB 56)
You are allowed to light from a Havdalla candle only after the Havdalla has been recited. (BeH “shedolkin”)
If a hefker object is found in a shul, rishonim dispute whether or not it belongs to the shul. (MB 59)
If a trustee of the shul has accepted a donated object (e.g. paroches) the donor can demand to have his name inscribed upon it. (MB 59)
If a single individual funds the building of a shul and does not allow others to pitch in because he wants the fame for himself, it could cause destruction to his children. (MB 59)
A trustee who merely oversees the restoration of a shul but does not spend money or work physically to make the refurbishment – does not deserve a plaque with his name on it. (MB 59)