Can I donate money set aside for ma’aser kesafim to Kehillas Shivtei Yeshurun?
Anyone (whether a member or not) can donate money towards the building of the KSY library and deduct it – like any other donation for a devar mitzvoh – from his or her ma’aser kesofim.
The restriction on a devar mitzvoh is that if the neder to donate was made first without the intention to use maos ma’aser to cover it, then strictly speaking,ma’aser cannot be used to cover it. Only if, at the time of the neder, the donor was planning to use his maos ma’aser can it be taken from ma’aser money.
In KSY, aliyos are not sold and an oleh is not required to give a donation at all. Only if he requests a second mi shebeirach is a donation expected. Hence, whatever donation is offered for the shul or library can be deducted from ma’aser if the olehhad that intention at the time of the neder.
Alternatively, many people never accepted upon themselves the stricter laws ofma’aser kesofim and always have used ma’aser money to pay for divrei mitzvoh. This behavior is acceptable and makes them free to deduct library nedorim and donations for other divrei mitzvoh from their ma’aser.